Designer:
Dan Poinsett

Project Category:
Bookshelf Speakers

Project Level:
Beginner

Project Time:
8-20 Hours

Project Cost:
$100 – $500

Project Description:
The Baronettes are a simple, no frills, 2-way stand mount speaker with a minimal crossover and outstanding neutrality.

Design Goals:
This project was a little less ambitious than some of my previous projects, but I still had a couple goals at the outset that I wanted to satisfy:

1) I had never used a Morel driver or a Dynavox driver. I had heard good things about both brands and wanted to give them a try. I chose a mid-level Morel tweeter and the mid-sized Dynavox woofer to experiment with.

2) I wanted to make a subtle differentiation in the crossover to focus on the smoothness of the roll-offs of the drivers over the phase integration between the two drivers to see what effect this would have on listening impressions.

Driver Selection:
As stated before, I chose these drivers based on the desire to experiment with them specifically. Of course the preliminary data suggested that they would work together well to make a relatively full range 2-way. The drivers are:

Morel CAT 308 1-1/8″ Tweeter

and

Dynavox LW6004PMR 6-1/2″ Woofer

Enclosure Design:
The initial plan, based on the published specs, was to use the Dynavox woofer in a ported enclosure to reach down around the mid 40s. Even the published Qts was a little high for this at .58, but I thought I’d give it a try. After receiving the woofers and measuring them both at .70, I decided to switch over to a sealed design. Since I was really looking for midrange fidelity out of the Dynavox driver and not trying to find the next 6″ subwoofer, this was a fine compromise for me.

I figured a 1/2 cu ft enclosure would give me a decent sized stand mount speaker with an F3 of about 60Hz and a Qtc of 0.85 to add a little warmth to the bottom end. The dimensions are 14″H x 8.5″W x 12″D, made of 3/4″ material and a 1″ thick baffle.

Enclosure Assembly:
This would be an easy build under any circumstances – it’s a simple sealed rectangular prism with the dimensions above – but it was very easy in my case as I used one of the pre-fab Dayton Audio cabinets as can be seen in the pictures. As such, I have no constuction pics or tips on this project, but again, this is a very simple sealed box. There is a 3/4″ roundover on the front baffle, which is nice, but 1/2″ would do nicely as well. The drivers are flush mounted and the crossover is mounted on the back wall of the enclosure. I lined the walls with open cell “egg crate” foam and loosely filled the cavities with polyfill. The enclosure dimensions and driver positions are shown in one of the pictures provided.

Crossover Design:
This is where some cool things happened and where, I believe, the magic of this design occurred. As I said earlier, I wanted to focus on making the roll-offs of the drivers as smooth as possible at the crossover point, only checking phase integration afterward to see if I was “close enough”. To this end, I was prepared to throw a lot of components at the situation if needed. I immediately started working with 3rd order electrical topologies with zobels looking for that perfect roll-off, thinking that with more components, I would have more control over the curve.

As it turned out, the drivers were so well behaved to begin with, that the smoothest curves were obtained on both drivers with a simple 2nd order filter on each. A 2-resistor L-pad was added to the tweeter circuit to bring the levels in line, but a simple cap and coil on each provided the best roll-off. I have included a zoomed out FR graph to see just how smooth the roll-offs are.

I used parts I already had on hand, which are decent quality, and the parts I recommended below are decent quality as well, but having a parts count this low opens the door for using really high quality components without blowing your budget. In the crossover schematic, I have assigned a resistance value to each of the inductors. This is the value of the inductors I used, but the design is not sensitive to these values so using better inductors should only make it sound better. With only 6 components per side, this may be a good design to experiment with boutique caps and coils.

Tips & Tricks:
Not many tips to offer here. The drivers are straightforward and the crossover simple. I did chamfer the backs of the woofer hole for improved airflow and the tweeter hole for easier access to the terminals.

Conclusion:
I’ll just come right out and say it. I love these speakers. They are the most neutral speakers I have ever built, without being the least bit lifeless. They are the most satisfying at low volumes of any speaker I have built. They aren’t the last word in output or bass extension (although a subwoofer would solve both of those problems), but I find myself attracted to my entire music collection again as EVERYTHING sounds great on these – not just the well recorded stuff. So with this in mind, and circling back to the goals, I’m actually not sure which is the stronger contributor to this listening experience.

1) I wanted to try the drivers. I tried the drivers. I love the drivers. They’re both very well made, very easy to work with in all regards, and produced an end result that I couldn’t be happier with. I’m going to say that the tweeter is the best tweeter that I’ve worked with personally (grain of salt: it’s also among the most expensive that I’ve worked with personally – I’ve never worked with $100+ tweeters), and besides the high Qts, there’s just nothing to complain about in the woofer. It has a beautiful neutral midrange and dynamic bass despite its minimal Xmax. It’s a beautifully made driver as well – kind of a shame to hide its backside in the enclosure.

2) I wanted to prioritize roll-off smoothness over phase integration. I did so. The phase integration was still decent, as can be implied from the reverse null overlaid in the FR graph, but the driver phases did not track for very far on either side of the xo point as I usually try for, nor did this tracking maintain itself well as you move from the design axis. I could have easily improved both of these areas, but doing so resulted in more peaks or a sharper knee in the roll-off so I opted for smoothness as intended. As stated earlier, this speaker is incredibly neutral with few enough offenses that I think I can chalk them up to poor recordings or mixes when they do occur. I don’t know if I can ascribe this to the smoothness-over-phase choice, but I know I will continue to make this choice on future builds until the data tells me to go the other way. I have a feeling it won’t.

About the Designer:
I am a member of the Speaker Building Design Team.

Project Parts List

Designer:
John H

Project Category:
Bookshelf Speakers

Project Level:
Intermediate

Project Time:
8-20 Hours

Project Cost:
$100 – $500

Project Description:
This project is a horizontal MTM center channel design that can also be used as vertical main speakers. This design has two crossovers, one for stand mounts, and one for locations like a center channel near boundaries like walls, corners, and screens.

Design Goals:
The goal of this design is to make a center channel speaker that can also be used as a main speaker. To improve off axis performance truncated frame drivers are used to get the driver spacing as close as possible. The truncated frame drivers are difficult to flush mount so the drivers are rear mounted.

Driver Selection:
The drivers are the Dayton RS150T-8 woofer, and the Dayton RS26A aluminum dome tweeter.

The RS28A tweeter is used as it can be crossed below 2,000 Hz. The dual RS150T-8 will be able to reach 100 dB with less than 10 watts.

Parts Used:
Udique stand mount pair
275-130 Dayton Audio RS28A-4 1-1/8″ Aluminum Dome Tweeter 2
275-138 Dayton Audio RS28TF Truncated Faceplate for RS Tweeters 2
295-342 Dayton Audio RS150T-8 6″ Reference Woofer Truncated Frame 4
260-387 Speaker Cabinet Port Tube 2″ ID Adjustable 2
260-311 Gold Banana 5-Way Binding Post Round Recessed Speaker Terminal Cup 2
260-317 Acousta-Stuf Polyfill Speaker Cabinet Sound Damping Material 1 lb. Bag 1

Crossover, Udique stand mount pair
004-2.7 Dayton Audio DNR-2.7 2.7 Ohm 10W Precision Audio Grade Resistor 2
004-2.4 Dayton Audio DNR-2.4 2.4 Ohm 10W Precision Audio Grade Resistor 2
027-429 Dayton Audio DMPC-7.5 7.5uF 250V Polypropylene Capacitor 2
255-028 Jantzen 1832 0.30mH 20 AWG Air Core Inductor 2
255-256 Jantzen Audio 1.3mH 18 AWG Air Core Inductor Crossover Coil 2
027-440 Dayton Audio DMPC-30 30uF 250V Polypropylene Capacitor 2

Description, Udique Center channel & corner placement
275-130 Dayton Audio RS28A-4 1-1/8″ Aluminum Dome Tweeter 1
275-138 Dayton Audio RS28TF Truncated Faceplate for RS Tweeters 1
295-342 Dayton Audio RS150T-8 6″ Reference Woofer Truncated Frame 2
260-387 Speaker Cabinet Port Tube 2″ ID Adjustable 1
260-311 Gold Banana 5-Way Binding Post Round Recessed Speaker Terminal Cup 1
260-317 Acousta-Stuf Polyfill Speaker Cabinet Sound Damping Material 1 lb. Bag 1

Crossover, Udique Center channel & corner placement
027-429 Dayton Audio DMPC-7.5 7.5uF 250V Polypropylene Capacitor 1
255-028 Jantzen 1832 0.30mH 20 AWG Air Core Inductor 1
255-250 Jantzen Audio 1.0mH 18 AWG Air Core Inductor Crossover Coil 1
027-440 Dayton Audio DMPC-30 30uF 250V Polypropylene Capacitor 1

Enclosure Design:
The design is a 20 liter volume ½ inch MDF box with a removable front baffle. This project had a “not to exceed” width of 7 inches for a specific location. This necessitated the use of ½ inch MDF for the sides to fit the RS150T frames. Future builders should consider ¾ inch MDF for the sides and increasing the baffle width to 7 ½ inches. The ½ inch MDF enclosure uses multiple side to side post braces.

The front baffle is 7.0 inches wide by 16 inches high. The front baffle has a 1/2 inch round over on all sides. Recess mounting the truncated frames would be difficult so all the drivers are rear mounted on a ½ inch thick front baffle. The tweeter opening has ½ inch round over. The woofer opening has a 3/8 inch 45 degree chamfer or it can use a ½ inch round over as well. The box is 14.77 inches deep.

The port is a Dayton adjustable 2 inch port mounted on the back of the cabinet. The port outer sleeve is completely closed and glued to the inner tube. The tubes are cut to 4 inches in length. This gives a box tuning of 47 Hz, and a F3 of 52.

Where a rear port would be a problem the box can be sealed. The volume can be decreased to as little as 10 liters by reducing the box depth. The F3 will be between 98 Hz and 93 Hz.

Enclosure Assembly:
The box is cut with 45 degree angles for all the corner joints except the front baffle. The 45 degree joints while more difficult to cut, eliminate the joint ghosting through the paint or veneer.

Here are a few steps/ tips that might help with the assembly

1. Add baffle mounting blocks and any braces before trimming the front baffle to fit. If you are veneering add the veneer to the outside of the cabinet or several layers of tape to approximate the thickness of the veneer.
2. Cut front baffle oversize and temporally secure it to the cabinet box with 2-3 small dabs of hot glue.
3. Route the baffle flush with the edge of the cabinet. This matches the cabinet to the baffle. Don’t remove the baffle from the cabinet yet.
4. With the square edged baffle, layout and mark the driver holes and the baffle mounting screw locations.
5. With a 1/16th inch bit, drill pilot holes for the baffle mounting screws through the baffle and into the mounting blocks.
6. Route the ½ inch round over on the front baffle.
7. Remove the front baffle by cutting through the hot glue spots with a thin blade putty knife. Mark the baffle to each box so it can be attached in the same position after cutting the driver holes and finishing.
8. Measure the drivers before determining the driver opening diameters.
9. Use C clamps to hold the drivers centered in the openings to mark the mounting holes
10. The drivers need to be sealed to the baffle with gaskets

To enable the ½ inch round-over to be added to the tweeter opening, temporarily secure scrap wood to the back of the baffle before drilling the 1 3/4 inch hole for the tweeter. The extra thickness will allow the router bushing to ride on MDF to cut the round-over at the full ½ inch depth.

The woofer opening receive a chamfer or a round over. To secure the baffle to the cabinet use a cap head wood screw with a washer or use a black pocket screw. Adjust the screw recess opening diameter in the baffle face to fit the washer or pocket screw head.

Insulate the box interior with 8 oz. of insulation (fiberglass or Fiberfill). Take care not to block the woofer rear vent or the port opening. I like to make pillows with poly batting then stuff them with insulation.

Mount the crossover on a board and screw to the bottom of the cabinet.

Crossover Design:
The crossover is a parallel configuration. After several iterations, the final crossovers are 4th order slopes with a crossover point of about 1,800 Hz. The horizontal center channel off axis performance with the speaker above or below a screen is good out to about 20 degrees off axis.

The crossover has two versions one for mounting the speakers on a stand away from a wall and another for mounting in a horizontal center channel location or vertically near a corner wall, screen, or corner.

For power handling the padding resistors on the tweeter are wired in parallel to give 1.3 ohms and 20 watts.

As the RS tweeters can vary in sensitivity. The center channel & corner placement crossover can have an optional 0.5 ohm resistor added if the sound is too bright.

Tips & Tricks:
Plug the rear port with a sock when the port is within 3 inches of a wall.

Conclusion:
The RS28A tweeter and RS150 is a nice sounding combination. The MTM has the power handling to fill most rooms. This speaker will be a good fit for most home theater systems.

About the Designer:
John is a member of the Speaker Building Design Team

Project Parts List

Designer:
Javad Shadzi

Project Category:
Tower Speakers

Project Level:
Intermediate

Project Time:
20+ Hours

Project Cost:
Over $1,000

Project Description:
The RS4 Speakers

I dubbed these speakers the RS4s, apparently Infinity has a discontinued speaker called the RS-4, oh well I’ve got a good lawyer, gonna roll the dice

RS4 hearkens to two things, the first is that I’ll be using mostly Dayton Reference Series drivers and it’s a 4-way system, the second is that I am an Audi tuner by trade and the Audi RS line of vehicles represent dynamically precisely what I’d like to achieve with these speakers acoustically.

The components I’ve chosen were based on many reviews and research I did, as well as considering this is my first set of speakers in 15 years, you gotta start somewhere right?

I don’t know what these are technically classified as, but they are basically an MTM with an added mid-bass 8″ and a 10″ subwoofer. Since I talked the wife into giving me the Dining Room I realized the potential to make something bigger and not limited size wise, so at that point I stopped planning a separate subwoofer and decided to integrate the sub-bass into the towers.

Design Goals:
The goals of this speaker build were several:
1 – A set of full range towers that could get very loud with low distortion.
2 – Utilize the latest technology in electronics including DSP cross over and room measured equalization.
3 – Something that looked sexy as heck and would be a real conversation starter.
4 – Not a bookshelf speaker but as compact as possible while delivering much larger performance.

Driver Selection:
Tweeter
XT25TG30-04 – I am a die hard Vifa fan from way back, obviously they’ve gone through some changes but I at least really wanted to try the newer tweeters they came out with. I chose these for a few reasons:
– Visually they match the rest of the RS drivers with their phase plug (I know…)
– They are 4ohms and have very high power handling, I want these to get loud and am really hoping these tweeters keep up. I was seriously considering two 8ohm tweeters in parallel but after researching the lobing issues, decided against it.
– Very well rated and used in some very high end commercial speakers

Crossover will start in the 3500kHz range

Midrange
RS100-8 – Since I was committed to the RS line so it was a matter of picking one of the options, I wanted to spread the audio load over multiple drivers whenever possible and the midrange posed the best opportunity. Was interested in the RS52 and will try them for a future project. The RS100 were very well rated, had the right power handling, impedance, etc. I was also intrigued with playing these drivers high frequency capabilities given the digital setup I’d have, will be fun to experiment bringing these in with the tweeter as well as seeing how they sound w/o it.

These will have about .08 ft3 of space, I’m considering crossing them over in the 600-3500 range.

Mid-Bass
RS225-4 – Something I really appreciate in a speaker is punchy mid-bass in that 100-300Hz range, I toyed with the idea of doing multiple 6.5″ options per cabinet (was very intrigued with the Tang Bang 6.5″ W6 at one point) but ultimately decided one 8″ per cabinet would do nicely. This is obviously a very well rated woofer and I’m looking forward to using it.

This will live in about .45 ft3, sealed, cross over in the 150-600 range.

Subwoofer
RSS265HF-4 – This driver was the most excruciating to make a decision on. The ride you go on when choosing a subwoofer driver isn’t one you are in control of, you are simply along for the ride as your brain is tortured with a decision that really cannot ever be made, the decision simply wears you down until your spirit is broken.

The RSS265HF ultimately met all the criteria including DNA, price and rating. I went back and forth a lot on enclosure style and ultimately decided that for simplicity and space sake, I’d stick to a sealed enclosure. Also with the very powerful DSP and amplification I had available, I figured I could make up for any loss of low end easily. Also this isn’t an HT setup so really I’m looking for fast, precise and powerful bass, not looking to simulate death star explosions, more the resonant impact of Sting’s bass string.

This driver will get about .8 ft3 and play between about 25-150Hz

Enclosure Design:
At my company 034Motorsport we use 3D printing technology and that got me thinking, it would be neat to do something a little different and not need to use a table saw. Using the “trans lam” technique I designed a set of enclosures that were made from 14 layers of .75″ maple plywood each. Each layer’s shape determined the overall shape of each enclosure as they were layered together.

Enclosure Assembly:
What I ended up with was 14 layers in each enclosure:
– 4 inner panels that created the very center of the enclosure as well as the volume for the mid/tweeter section. ID of this enclosure is .75x 4 or 3″
– 2 outer/inner panels that created the sides of the mid/tweeter section as well as additional inner layers for the lower part of the enclosure.
– 4 inner/lower panels that added more space for the lower part of the woofer/sub enclosure.
– 4 outer/lower panels that capped the woofer/sub enclosure and created a 1.5″ wall thickness for the outside.

All enclosures have 1.5″ wall thickness except for the mid/tweeter section which has 1.5″ wall top, back and bottom, but .75 on the sides.

Of the two different inner and outer panels, the first one of each that I created acted as the pattern for additional units and layers. That way every layer was the same and I didn’t have to worry about not having a table saw to make accurate cuts with. My plan was to create the first inner piece, then glue additional oversized panes to that and flush router each additional layer that is added and work from the inside out. And it worked!

All in all I needed almost 5 full sheets of plywood, I chose Maple as it was the only option at Home Depot that was actually .75″ thick, and I need all the thickness I can get for this!

Crossover Design:
After adding up the cost of doing a passive network for these, I quickly realized I could put a significant piece of cash towards a fully digital system with an amplifier section for each driver.

I ended up with a miniDSP 4×10 which allows for 2 inputs and 8 analog outputs, one pair for each subwoofer, woofer, midrange and tweeter.

Each driver operates in the following range:
– Subwoofer, 20-150hz
– Midbass – 150-600hz
– Midrange – 600-3500hz
– Tweeter – 3500-20,000+hz

The following Adcom components are being used with the miniDSP:

– GFA-545II – 150w x 2 in 4ohms – Mid-bass Section
– GFA-555 – 325w x 2 in 4ohms – Subwoofer Section
– GFA-2535 – 90w x 4 in 4ohms – Midrange and Tweeter Section
– GFP-565 – Preamp

Tips & Tricks:
If you’re interested in buliding these or something similar, post in my thread in Parts Express’ Tech Talk Forum, just search “Javad RS4″ or look me up as user JavadS.

Conclusion:
I couldn’t be happier with the results! The Dayton drivers lived up to everything everyone said about them, very clean and low distortion drivers. I have been told that these would hold their own with any commercially built speaker in the $3-5000 range.

The imaging of these speakers is what really blows me away, closing my eyes during Dark Side of the Moon or a live recorded Jazz piece allows me to virtually see and touch each instrument.

I never knew it rained in the last half of Imogen Heap’s Hide and Seek, I had to pause the music as I thought it had started to rain outside. This astounded me as I’d heard this song hundreds of times before.

There are few things as satisfying as imagining a set of speakers, building them, getting lost in an album, even being brought to tears by the impact and realism of the music!

About the Designer:
Javad Shadzi is President of 034Motorsport, a company that engineers and manufactures high performance automotive products in Fremont, CA. Javad loves to cook and spend time with his beautiful wife and 3 kids (4th on the way!).

Though it’s been 15 years since he built a speaker, now that he’s built these he’s not sure he can stop anytime soon!

Project Parts List

Designer:
Jason

Project Category:
Portable Speakers

Project Level:
Intermediate

Project Time:
8-20 Hours

Project Cost:
$100 – $500

Project Description:
This is portable, bluetooth 4.0, battery-powered, tower speaker system.

Design Goals:
To design a portable audio system that was bluetooth capable, durable, and has excellent audio output and battery life.

Enclosure Design:
The front baffle is stained, birch plywood with several coats of polyurethane. The rest of the enclosure was sealed and protected with several Acry-Tech DuraTex available at PE. Front emblem was installed as a signature, and for fun.

Driver Selection:
AuraSound NS3-193-8A 3″ Extended Range Driver 8 Ohm

Enclosure Assembly:
Wood glue and clamps. No screws.

Crossover Design:
No filters added. Drivers run full-range

Tips & Tricks:
When using Acry-Tech DuraTex, make sure your enclosure is sanded and painted properly, leaving no blemishes because they will show through.

Conclusion:
After about 20+ listening hours, the sound quality is pleasing. Warm and inviting. The stage is large and if you’ve heard the NS3, you are aware of the detail these drivers produce. Much more low end than expected I’m guessing around 50 Hz. Battery life is about 8 hours at 50% volume listening to all genres of music. I imagine battery life would double listening to music with less demand from the driver.

About the Designer:
Owner of Hi-Fi Luggage which builds bluetooth speaker systems into vintage luggage. Also works as a Marriage and Family Therapist out of Orange County.

Project Parts List

Designer:
iammatt

Project Category:
Freestyle Speakers

Project Level:
Intermediate

Project Time:
8-20 Hours

Project Cost:
$100 – $500

Project Description:
This was originally planned to be a ‘shop stereo’ but ended up turning out better than i thought. so it’s going to live inside now. sounds great!

Design Goals:
I looked for components that would : take a small-ish enclosure, hold up to the elements, and simplify design.

Driver Selection:
I ended up with 3.5″ ‘full range’ alumn cone, rubber surround speakers for the left and right channels. They take a .15 cubic foot enclosure for vented application, so that was just about right for the size I wanted. They also get great reviews for being full range, so that meant I didn’t need a tweeter (which silk domes are cheap but dust would be brutal) or a crossover network. I tuned the box-size and port to center this guy on 65 htz. lots of web calculators and math here. Lots of back and forth.

For the subwoofer, I went with a 6.5″ sub, again with rubber surround. This one took a larger box (obvisouly) but relative to other options, its a small box. Lots and lots of x-max (cone travel) meant I could get deep bass. Again more web calculators and math to get box size and port length – here I wanted to dial in lower, I aimed for 35-40 htz.

For the amp, I originally was planning on a $20 lepai 2.1, but quickly decided to can it, because the thd on all channels was deplorable, and the included powersupply was under-driving (12v vs 14.4) meaning it would be a weakling out of the box. I opted instead for a 2.1 plate amplifier, which could be integrated into the back of the box easily. It also provides tons of clean power, relative to the price. 25 watts x 2, plus 50×1. I’m going to pick up another one of these and build a 2.1 system for my home office. It really sounds good.

Enclosure Design:
It took lots of paper to figure out how to orient these box requirements, amp cut-outs, etc to look good and sound good. That took a long time, and was many pages of scribble.

Enclosure Assembly:
Look ma, no screws! There are no nails or screws in the main enclsoure, which is made from 3/4 mdf, just dados and rabbits and gorilla glue (which is awesome for MDF boxes, because it foams up, sealing everything airtight)

The front panel is made from really really old shipping wood I salvaged from the attic of our garage. Apparently the old owner used to be a furniture maker, and kept all his broken down crate wood up there. I’ve been pulling nails from it and using it for various things around the house. It’s got a great patina I think. douglas fir? I dunno.

Conclusion:
Overall, I’m incredibly pleased with the build. The variable sub crossover let’s me fine tune exactly where I want the balance to be, and independent level controls on l/r and sub allow even more dial-in.

It sounds amazing, and the bass is really something – huge and deep. I’m really really impressed with that little sub.

The thing weighs about 50 lbs, so that helps too

Anyway, here’s a few videos of the sound quality, which don’t do it any justice at all.

https://www.youtube.com/watch?v=sj55Ylvzj3U

https://www.youtube.com/watch?v=B9cgkBD1qXA

https://www.youtube.com/watch?v=Njq_xtpzNuo

About the Designer:
I like building things that make beautiful noises.

Project Parts List

Designer:
Michael Alline

Project Category:
Loudspeakers/Cabinets

Project Level:
Intermediate

Project Time:
8-20 Hours

Project Cost:
$500 – $1,000

Project Description:
I needed heavy duty speakers for Mardi Gras parties.

Design Goals:
Speakers that won’t explode when cranked.

Driver Selection:
I used Matt Phillips “Rockin’ it Old School” drivers, enclosure, and crossovers.

Enclosure Assembly:
Painted the boxes with RattleBomb metallic automotive paint from rothmetalflake.com.

Tips & Tricks:
Search the Parts Express website for Rockin it old school for everything you need

Conclusion:
These are loud but detailed wonderful sounding speakers!

About the Designer:
I’m basically a woodworker. These are easy to assemble.

Project Category:
Tower Speakers

Project Level:
Advanced

Project Time:
20+ Hours

Project Cost:
$500 – $1,000

Project Description:
Mid sized line array with improved realism vertical image, low distortions and high power handling.
Bass response projected to 80hz.
Relatively small budget for line array, using low distortion buyout Fountek drivers within desirable passband.

Design Goals:
Affordable Line Array sound in a small package.

Driver Selection:
Tweeter

Midrange

Woofer

Enclosure Design:
Sealed enclosure for both midrange and woofer sections. Multiple bracing is highly recommended.
Drawings are for 3/4” thick material.

Crossover Design:
Crossover design is fairly straightforward. Tweeter array is represented by a single T1 driver as well as midrange array is represented by M1 driver and woofers, by W1. This is done so the crossover CAD screen is not cluttered with 16 drivers.
Wiring the array.
Tweeters.
Tweeters are numbered from the top to the bottom. Top tweeter is #1 and lower tweeter subsequently numbered #5. Tweeters #1,#2, #4 and #5 are wired in series to each other. This quartet is wired parallel to the center tweeter #3.
Midrange drivers.
There’s total of 9 drivers. They are wired in 3/series parallel so the final impedance is equal to a single driver. Easiest way to connect the drivers correctly is to lay out 3 groups of 3 drivers. Solder series connections in each group of 3 and then connect 3 groups, parallel.
Woofers.
Woofers are wired parallel to each other.

Tips & Tricks:
The heart of the system is Fountek’s FE87 2-1/2″ full range driver. By itself it has a fairly low sensitivity, limited x-max and limited low end response. The midrange, lower treble are however very extended and the driver even deeps in to upper bass. This extremely wide pass-band lands it perfectly for a line array where it will used in multiples and low sensitivity will not be an issue any longer. Wide response also allows it to be used with low crossed woofers on the bottom and small tweeter to extend the response cleanly all the way to 20khz and makes the crossover network easier to design.
7” Dayton Aluminum woofers were chosen to reinforce bottom end. Positioning them close to the floor will somewhat negate the need for baffle step compensation and using a pair will increase sensitivity and decrease distortions. This will also allow for the form factor of a speaker to remain a slim tower. Sealed alignment, in my opinion is preferred from the various points of view. For starters, it is the volume and appearance of the box. Secondly, ported design for this woofers will entertain the situation where the drivers will quickly overextend below port tuning frequency and may introduce distortions. Sealed response in to 80 hz on the integration hand, makes the use of the dedicated low crossed powered subwoofer easy.
Finally to the tweeters.
It’s a small dome with the neo motor. Using 5 tweeters in the array configuration may invite itself for shading the tweeters and altering vertical image of the speaker.

Box assembly.
Section, housing midrange drivers and the tweeters can be assembled separate. This is really up to the builder. One requirement to both, lower and upper compartment is extensive bracing. Because the upper section is fairly tall, it will produce standing wave. To negate the effect, it is recommended to use 5” or so of Rock-wool or Owen’s corning on the top and bottom of the midrange cabinet. The rest of the chamber can be filled with either Acustastuff (sold by Parts Express) or fiberglass if you don’t mind handling it. Woofer chamber also needs to be stuffed with Acustastuff or fiberglass.

Experiment with the R10 to your own preferences. I ended up using 10Ohm value in a fairly reverberant space. This lowered output of the midrange array by about 3.5 db.

Conclusion:
The system is up for a reviews by enthusiasts and will be shown on the upcoming NY/NJ DIY speaker fest.

About the Designer:
Roman Erlikh is a professional furniture maker and a speaker builder.
Roman also hosts NY/NJ DIY Speaker fest in Brooklyn Navy Yard.

Project Parts List

Designer:
Mike MacIsaac

Project Category:
Freestyle Speakers

Project Level:
Beginner

Project Time:
8-20 Hours

Project Cost:
$100 – $500

Project Description:
This is a unique “2.1” system inspired by the classic JBL 2397 “Smith Horn”. It cost less than $200, perhaps $125 in parts and maybe $75 for the wood.

Design Goals:
A small inexpensive 2.1 system, with a unique look. The shape of the Smith horns was copied for the subwoofer enclosure.

Driver Selection:
Two inexpensive full-range drivers. The Fountek FE87 was a good fit. One inexpensive subwoofer and amp. The HP-5210 5-1/4″ woofer and Dayton Audio SA25 25W seemed to also be a good fit.

Enclosure Design:
This was my first build, so I’m new at this. I tried to work the numbers and came up with 242 cu-in for the drivers and 345 cu-in for the subwoofer. I went with a cube for the drivers that ended up just under 7″, and the subwoofer also ended about 7″ tall.

Enclosure Assembly:
The driver cubes are 3/4″ x 3/4″ maple with 1/5″ plywood. The Smith horns are 1/2″ maple plywood with two 1/8″ bent maple strips glued to the front. The subwoofer is 3 pieces of 1/5″ plywood laminated together (many slots cut in the back of each to get the flexibility to bend). To try something different, I finished it with shellac. Not sure I’ll do that again, rather, go back to natural stain and 3 coats of polyurethane.

Crossover Design:
The only crossover is the low-pass built into the subwoofer amplifier.

Tips & Tricks:
Bending and gluing the plywood for the subwoofer enclosure was tricky. In the end having many cuts, maybe 3/8″ apart more than half way through the plywood allowed it to be bent with ease.

Conclusion:
For all the woodwork necessary, maybe I should have paid more for higher quality parts. But the sound is really nice, and that’s what counts.

About the Designer:
Newby speaker designer/builder, intermediate woodworker. Bringing the two together has been rewarding

Project Parts List

You will also need some inexpensive spiked feet…

Designer:
Dan Poinsett

Project Category:
Bookshelf Speakers

Project Level:
Beginner

Project Time:
8-20 Hours

Project Cost:
$100 – $500

Project Description:
The Baronettes are a simple, no frills, 2-way stand mount speaker with a minimal crossover and outstanding neutrality.

Design Goals:
This project was a little less ambitious than some of my previous projects, but I still had a couple goals at the outset that I wanted to satisfy:

1) I had never used a Morel driver or a Dynavox driver. I had heard good things about both brands and wanted to give them a try. I chose a mid-level Morel tweeter and the mid-sized Dynavox woofer to experiment with.

2) I wanted to make a subtle differentiation in the crossover to focus on the smoothness of the roll-offs of the drivers over the phase integration between the two drivers to see what effect this would have on listening impressions.

Driver Selection:
As stated before, I chose these drivers based on the desire to experiment with them specifically. Of course the preliminary data suggested that they would work together well to make a relatively full range 2-way. The drivers are:

Morel CAT 308 1-1/8″ Tweeter

and

Dynavox LW6004PMR 6-1/2″ Woofer

Enclosure Design:
The initial plan, based on the published specs, was to use the Dynavox woofer in a ported enclosure to reach down around the mid 40s. Even the published Qts was a little high for this at .58, but I thought I’d give it a try. After receiving the woofers and measuring them both at .70, I decided to switch over to a sealed design. Since I was really looking for midrange fidelity out of the Dynavox driver and not trying to find the next 6″ subwoofer, this was a fine compromise for me.

I figured a 1/2 cu ft enclosure would give me a decent sized stand mount speaker with an F3 of about 60Hz and a Qtc of 0.85 to add a little warmth to the bottom end. The dimensions are 14″H x 8.5″W x 12″D, made of 3/4″ material and a 1″ thick baffle.

Enclosure Assembly:
This would be an easy build under any circumstances – it’s a simple sealed rectangular prism with the dimensions above – but it was very easy in my case as I used one of the pre-fab Dayton Audio cabinets as can be seen in the pictures. As such, I have no constuction pics or tips on this project, but again, this is a very simple sealed box. There is a 3/4″ roundover on the front baffle, which is nice, but 1/2″ would do nicely as well. The drivers are flush mounted and the crossover is mounted on the back wall of the enclosure. I lined the walls with open cell “egg crate” foam and loosely filled the cavities with polyfill. The enclosure dimensions and driver positions are shown in one of the pictures provided.

Crossover Design:
This is where some cool things happened and where, I believe, the magic of this design occurred. As I said earlier, I wanted to focus on making the roll-offs of the drivers as smooth as possible at the crossover point, only checking phase integration afterward to see if I was “close enough”. To this end, I was prepared to throw a lot of components at the situation if needed. I immediately started working with 3rd order electrical topologies with zobels looking for that perfect roll-off, thinking that with more components, I would have more control over the curve.

As it turned out, the drivers were so well behaved to begin with, that the smoothest curves were obtained on both drivers with a simple 2nd order filter on each. A 2-resistor L-pad was added to the tweeter circuit to bring the levels in line, but a simple cap and coil on each provided the best roll-off. I have included a zoomed out FR graph to see just how smooth the roll-offs are.

I used parts I already had on hand, which are decent quality, and the parts I recommended below are decent quality as well, but having a parts count this low opens the door for using really high quality components without blowing your budget. In the crossover schematic, I have assigned a resistance value to each of the inductors. This is the value of the inductors I used, but the design is not sensitive to these values so using better inductors should only make it sound better. With only 6 components per side, this may be a good design to experiment with boutique caps and coils.

Tips & Tricks:
Not many tips to offer here. The drivers are straightforward and the crossover simple. I did chamfer the backs of the woofer hole for improved airflow and the tweeter hole for easier access to the terminals.

Conclusion:
I’ll just come right out and say it. I love these speakers. They are the most neutral speakers I have ever built, without being the least bit lifeless. They are the most satisfying at low volumes of any speaker I have built. They aren’t the last word in output or bass extension (although a subwoofer would solve both of those problems), but I find myself attracted to my entire music collection again as EVERYTHING sounds great on these – not just the well recorded stuff. So with this in mind, and circling back to the goals, I’m actually not sure which is the stronger contributor to this listening experience.

1) I wanted to try the drivers. I tried the drivers. I love the drivers. They’re both very well made, very easy to work with in all regards, and produced an end result that I couldn’t be happier with. I’m going to say that the tweeter is the best tweeter that I’ve worked with personally (grain of salt: it’s also among the most expensive that I’ve worked with personally – I’ve never worked with $100+ tweeters), and besides the high Qts, there’s just nothing to complain about in the woofer. It has a beautiful neutral midrange and dynamic bass despite its minimal Xmax. It’s a beautifully made driver as well – kind of a shame to hide its backside in the enclosure.

2) I wanted to prioritize roll-off smoothness over phase integration. I did so. The phase integration was still decent, as can be implied from the reverse null overlaid in the FR graph, but the driver phases did not track for very far on either side of the xo point as I usually try for, nor did this tracking maintain itself well as you move from the design axis. I could have easily improved both of these areas, but doing so resulted in more peaks or a sharper knee in the roll-off so I opted for smoothness as intended. As stated earlier, this speaker is incredibly neutral with few enough offenses that I think I can chalk them up to poor recordings or mixes when they do occur. I don’t know if I can ascribe this to the smoothness-over-phase choice, but I know I will continue to make this choice on future builds until the data tells me to go the other way. I have a feeling it won’t.

About the Designer:
I am a member of the Speaker Building Design Team.

Project Parts List

Designer:
John H

Project Category:
Bookshelf Speakers

Project Level:
Intermediate

Project Time:
8-20 Hours

Project Cost:
$100 – $500

Project Description:
This project is a horizontal MTM center channel design that can also be used as vertical main speakers. This design has two crossovers, one for stand mounts, and one for locations like a center channel near boundaries like walls, corners, and screens.

Design Goals:
The goal of this design is to make a center channel speaker that can also be used as a main speaker. To improve off axis performance truncated frame drivers are used to get the driver spacing as close as possible. The truncated frame drivers are difficult to flush mount so the drivers are rear mounted.

Driver Selection:
The drivers are the Dayton RS150T-8 woofer, and the Dayton RS26A aluminum dome tweeter.

The RS28A tweeter is used as it can be crossed below 2,000 Hz. The dual RS150T-8 will be able to reach 100 dB with less than 10 watts.

Parts Used:
Udique stand mount pair
275-130 Dayton Audio RS28A-4 1-1/8″ Aluminum Dome Tweeter 2
275-138 Dayton Audio RS28TF Truncated Faceplate for RS Tweeters 2
295-342 Dayton Audio RS150T-8 6″ Reference Woofer Truncated Frame 4
260-387 Speaker Cabinet Port Tube 2″ ID Adjustable 2
260-311 Gold Banana 5-Way Binding Post Round Recessed Speaker Terminal Cup 2
260-317 Acousta-Stuf Polyfill Speaker Cabinet Sound Damping Material 1 lb. Bag 1

Crossover, Udique stand mount pair
004-2.7 Dayton Audio DNR-2.7 2.7 Ohm 10W Precision Audio Grade Resistor 2
004-2.4 Dayton Audio DNR-2.4 2.4 Ohm 10W Precision Audio Grade Resistor 2
027-429 Dayton Audio DMPC-7.5 7.5uF 250V Polypropylene Capacitor 2
255-028 Jantzen 1832 0.30mH 20 AWG Air Core Inductor 2
255-256 Jantzen Audio 1.3mH 18 AWG Air Core Inductor Crossover Coil 2
027-440 Dayton Audio DMPC-30 30uF 250V Polypropylene Capacitor 2

Description, Udique Center channel & corner placement
275-130 Dayton Audio RS28A-4 1-1/8″ Aluminum Dome Tweeter 1
275-138 Dayton Audio RS28TF Truncated Faceplate for RS Tweeters 1
295-342 Dayton Audio RS150T-8 6″ Reference Woofer Truncated Frame 2
260-387 Speaker Cabinet Port Tube 2″ ID Adjustable 1
260-311 Gold Banana 5-Way Binding Post Round Recessed Speaker Terminal Cup 1
260-317 Acousta-Stuf Polyfill Speaker Cabinet Sound Damping Material 1 lb. Bag 1

Crossover, Udique Center channel & corner placement
027-429 Dayton Audio DMPC-7.5 7.5uF 250V Polypropylene Capacitor 1
255-028 Jantzen 1832 0.30mH 20 AWG Air Core Inductor 1
255-250 Jantzen Audio 1.0mH 18 AWG Air Core Inductor Crossover Coil 1
027-440 Dayton Audio DMPC-30 30uF 250V Polypropylene Capacitor 1

Enclosure Design:
The design is a 20 liter volume ½ inch MDF box with a removable front baffle. This project had a “not to exceed” width of 7 inches for a specific location. This necessitated the use of ½ inch MDF for the sides to fit the RS150T frames. Future builders should consider ¾ inch MDF for the sides and increasing the baffle width to 7 ½ inches. The ½ inch MDF enclosure uses multiple side to side post braces.

The front baffle is 7.0 inches wide by 16 inches high. The front baffle has a 1/2 inch round over on all sides. Recess mounting the truncated frames would be difficult so all the drivers are rear mounted on a ½ inch thick front baffle. The tweeter opening has ½ inch round over. The woofer opening has a 3/8 inch 45 degree chamfer or it can use a ½ inch round over as well. The box is 14.77 inches deep.

The port is a Dayton adjustable 2 inch port mounted on the back of the cabinet. The port outer sleeve is completely closed and glued to the inner tube. The tubes are cut to 4 inches in length. This gives a box tuning of 47 Hz, and a F3 of 52.

Where a rear port would be a problem the box can be sealed. The volume can be decreased to as little as 10 liters by reducing the box depth. The F3 will be between 98 Hz and 93 Hz.

Enclosure Assembly:
The box is cut with 45 degree angles for all the corner joints except the front baffle. The 45 degree joints while more difficult to cut, eliminate the joint ghosting through the paint or veneer.

Here are a few steps/ tips that might help with the assembly

1. Add baffle mounting blocks and any braces before trimming the front baffle to fit. If you are veneering add the veneer to the outside of the cabinet or several layers of tape to approximate the thickness of the veneer.
2. Cut front baffle oversize and temporally secure it to the cabinet box with 2-3 small dabs of hot glue.
3. Route the baffle flush with the edge of the cabinet. This matches the cabinet to the baffle. Don’t remove the baffle from the cabinet yet.
4. With the square edged baffle, layout and mark the driver holes and the baffle mounting screw locations.
5. With a 1/16th inch bit, drill pilot holes for the baffle mounting screws through the baffle and into the mounting blocks.
6. Route the ½ inch round over on the front baffle.
7. Remove the front baffle by cutting through the hot glue spots with a thin blade putty knife. Mark the baffle to each box so it can be attached in the same position after cutting the driver holes and finishing.
8. Measure the drivers before determining the driver opening diameters.
9. Use C clamps to hold the drivers centered in the openings to mark the mounting holes
10. The drivers need to be sealed to the baffle with gaskets

To enable the ½ inch round-over to be added to the tweeter opening, temporarily secure scrap wood to the back of the baffle before drilling the 1 3/4 inch hole for the tweeter. The extra thickness will allow the router bushing to ride on MDF to cut the round-over at the full ½ inch depth.

The woofer opening receive a chamfer or a round over. To secure the baffle to the cabinet use a cap head wood screw with a washer or use a black pocket screw. Adjust the screw recess opening diameter in the baffle face to fit the washer or pocket screw head.

Insulate the box interior with 8 oz. of insulation (fiberglass or Fiberfill). Take care not to block the woofer rear vent or the port opening. I like to make pillows with poly batting then stuff them with insulation.

Mount the crossover on a board and screw to the bottom of the cabinet.

Crossover Design:
The crossover is a parallel configuration. After several iterations, the final crossovers are 4th order slopes with a crossover point of about 1,800 Hz. The horizontal center channel off axis performance with the speaker above or below a screen is good out to about 20 degrees off axis.

The crossover has two versions one for mounting the speakers on a stand away from a wall and another for mounting in a horizontal center channel location or vertically near a corner wall, screen, or corner.

For power handling the padding resistors on the tweeter are wired in parallel to give 1.3 ohms and 20 watts.

As the RS tweeters can vary in sensitivity. The center channel & corner placement crossover can have an optional 0.5 ohm resistor added if the sound is too bright.

Tips & Tricks:
Plug the rear port with a sock when the port is within 3 inches of a wall.

Conclusion:
The RS28A tweeter and RS150 is a nice sounding combination. The MTM has the power handling to fill most rooms. This speaker will be a good fit for most home theater systems.

About the Designer:
John is a member of the Speaker Building Design Team

Project Parts List

Designer:
Javad Shadzi

Project Category:
Tower Speakers

Project Level:
Intermediate

Project Time:
20+ Hours

Project Cost:
Over $1,000

Project Description:
The RS4 Speakers

I dubbed these speakers the RS4s, apparently Infinity has a discontinued speaker called the RS-4, oh well I’ve got a good lawyer, gonna roll the dice

RS4 hearkens to two things, the first is that I’ll be using mostly Dayton Reference Series drivers and it’s a 4-way system, the second is that I am an Audi tuner by trade and the Audi RS line of vehicles represent dynamically precisely what I’d like to achieve with these speakers acoustically.

The components I’ve chosen were based on many reviews and research I did, as well as considering this is my first set of speakers in 15 years, you gotta start somewhere right?

I don’t know what these are technically classified as, but they are basically an MTM with an added mid-bass 8″ and a 10″ subwoofer. Since I talked the wife into giving me the Dining Room I realized the potential to make something bigger and not limited size wise, so at that point I stopped planning a separate subwoofer and decided to integrate the sub-bass into the towers.

Design Goals:
The goals of this speaker build were several:
1 – A set of full range towers that could get very loud with low distortion.
2 – Utilize the latest technology in electronics including DSP cross over and room measured equalization.
3 – Something that looked sexy as heck and would be a real conversation starter.
4 – Not a bookshelf speaker but as compact as possible while delivering much larger performance.

Driver Selection:
Tweeter
XT25TG30-04 – I am a die hard Vifa fan from way back, obviously they’ve gone through some changes but I at least really wanted to try the newer tweeters they came out with. I chose these for a few reasons:
– Visually they match the rest of the RS drivers with their phase plug (I know…)
– They are 4ohms and have very high power handling, I want these to get loud and am really hoping these tweeters keep up. I was seriously considering two 8ohm tweeters in parallel but after researching the lobing issues, decided against it.
– Very well rated and used in some very high end commercial speakers

Crossover will start in the 3500kHz range

Midrange
RS100-8 – Since I was committed to the RS line so it was a matter of picking one of the options, I wanted to spread the audio load over multiple drivers whenever possible and the midrange posed the best opportunity. Was interested in the RS52 and will try them for a future project. The RS100 were very well rated, had the right power handling, impedance, etc. I was also intrigued with playing these drivers high frequency capabilities given the digital setup I’d have, will be fun to experiment bringing these in with the tweeter as well as seeing how they sound w/o it.

These will have about .08 ft3 of space, I’m considering crossing them over in the 600-3500 range.

Mid-Bass
RS225-4 – Something I really appreciate in a speaker is punchy mid-bass in that 100-300Hz range, I toyed with the idea of doing multiple 6.5″ options per cabinet (was very intrigued with the Tang Bang 6.5″ W6 at one point) but ultimately decided one 8″ per cabinet would do nicely. This is obviously a very well rated woofer and I’m looking forward to using it.

This will live in about .45 ft3, sealed, cross over in the 150-600 range.

Subwoofer
RSS265HF-4 – This driver was the most excruciating to make a decision on. The ride you go on when choosing a subwoofer driver isn’t one you are in control of, you are simply along for the ride as your brain is tortured with a decision that really cannot ever be made, the decision simply wears you down until your spirit is broken.

The RSS265HF ultimately met all the criteria including DNA, price and rating. I went back and forth a lot on enclosure style and ultimately decided that for simplicity and space sake, I’d stick to a sealed enclosure. Also with the very powerful DSP and amplification I had available, I figured I could make up for any loss of low end easily. Also this isn’t an HT setup so really I’m looking for fast, precise and powerful bass, not looking to simulate death star explosions, more the resonant impact of Sting’s bass string.

This driver will get about .8 ft3 and play between about 25-150Hz

Enclosure Design:
At my company 034Motorsport we use 3D printing technology and that got me thinking, it would be neat to do something a little different and not need to use a table saw. Using the “trans lam” technique I designed a set of enclosures that were made from 14 layers of .75″ maple plywood each. Each layer’s shape determined the overall shape of each enclosure as they were layered together.

Enclosure Assembly:
What I ended up with was 14 layers in each enclosure:
– 4 inner panels that created the very center of the enclosure as well as the volume for the mid/tweeter section. ID of this enclosure is .75x 4 or 3″
– 2 outer/inner panels that created the sides of the mid/tweeter section as well as additional inner layers for the lower part of the enclosure.
– 4 inner/lower panels that added more space for the lower part of the woofer/sub enclosure.
– 4 outer/lower panels that capped the woofer/sub enclosure and created a 1.5″ wall thickness for the outside.

All enclosures have 1.5″ wall thickness except for the mid/tweeter section which has 1.5″ wall top, back and bottom, but .75 on the sides.

Of the two different inner and outer panels, the first one of each that I created acted as the pattern for additional units and layers. That way every layer was the same and I didn’t have to worry about not having a table saw to make accurate cuts with. My plan was to create the first inner piece, then glue additional oversized panes to that and flush router each additional layer that is added and work from the inside out. And it worked!

All in all I needed almost 5 full sheets of plywood, I chose Maple as it was the only option at Home Depot that was actually .75″ thick, and I need all the thickness I can get for this!

Crossover Design:
After adding up the cost of doing a passive network for these, I quickly realized I could put a significant piece of cash towards a fully digital system with an amplifier section for each driver.

I ended up with a miniDSP 4×10 which allows for 2 inputs and 8 analog outputs, one pair for each subwoofer, woofer, midrange and tweeter.

Each driver operates in the following range:
– Subwoofer, 20-150hz
– Midbass – 150-600hz
– Midrange – 600-3500hz
– Tweeter – 3500-20,000+hz

The following Adcom components are being used with the miniDSP:

– GFA-545II – 150w x 2 in 4ohms – Mid-bass Section
– GFA-555 – 325w x 2 in 4ohms – Subwoofer Section
– GFA-2535 – 90w x 4 in 4ohms – Midrange and Tweeter Section
– GFP-565 – Preamp

Tips & Tricks:
If you’re interested in buliding these or something similar, post in my thread in Parts Express’ Tech Talk Forum, just search “Javad RS4″ or look me up as user JavadS.

Conclusion:
I couldn’t be happier with the results! The Dayton drivers lived up to everything everyone said about them, very clean and low distortion drivers. I have been told that these would hold their own with any commercially built speaker in the $3-5000 range.

The imaging of these speakers is what really blows me away, closing my eyes during Dark Side of the Moon or a live recorded Jazz piece allows me to virtually see and touch each instrument.

I never knew it rained in the last half of Imogen Heap’s Hide and Seek, I had to pause the music as I thought it had started to rain outside. This astounded me as I’d heard this song hundreds of times before.

There are few things as satisfying as imagining a set of speakers, building them, getting lost in an album, even being brought to tears by the impact and realism of the music!

About the Designer:
Javad Shadzi is President of 034Motorsport, a company that engineers and manufactures high performance automotive products in Fremont, CA. Javad loves to cook and spend time with his beautiful wife and 3 kids (4th on the way!).

Though it’s been 15 years since he built a speaker, now that he’s built these he’s not sure he can stop anytime soon!

Project Parts List

Designer:
Jason

Project Category:
Portable Speakers

Project Level:
Intermediate

Project Time:
8-20 Hours

Project Cost:
$100 – $500

Project Description:
This is portable, bluetooth 4.0, battery-powered, tower speaker system.

Design Goals:
To design a portable audio system that was bluetooth capable, durable, and has excellent audio output and battery life.

Enclosure Design:
The front baffle is stained, birch plywood with several coats of polyurethane. The rest of the enclosure was sealed and protected with several Acry-Tech DuraTex available at PE. Front emblem was installed as a signature, and for fun.

Driver Selection:
AuraSound NS3-193-8A 3″ Extended Range Driver 8 Ohm

Enclosure Assembly:
Wood glue and clamps. No screws.

Crossover Design:
No filters added. Drivers run full-range

Tips & Tricks:
When using Acry-Tech DuraTex, make sure your enclosure is sanded and painted properly, leaving no blemishes because they will show through.

Conclusion:
After about 20+ listening hours, the sound quality is pleasing. Warm and inviting. The stage is large and if you’ve heard the NS3, you are aware of the detail these drivers produce. Much more low end than expected I’m guessing around 50 Hz. Battery life is about 8 hours at 50% volume listening to all genres of music. I imagine battery life would double listening to music with less demand from the driver.

About the Designer:
Owner of Hi-Fi Luggage which builds bluetooth speaker systems into vintage luggage. Also works as a Marriage and Family Therapist out of Orange County.

Project Parts List

Designer:
Scott Sehlin

Project Category:
Tower Speakers

Project Level:
Intermediate

Project Time:
20+ Hours

Project Cost:
$100 – $500

Project Description:
I’m sure this is the case for many of us… The inspiration for some of my audio projects and acquisitions involves things I wished I could have either afforded or accommodated “back in the day”. I started scraping together audio equipment and perusing audio magazines back in the late 1970’s and early 80’s. My first major speaker upgrade from the cheap and loud 3-ways I purchased while in high school was a pair of Infinity RS-5000’s that I picked up in the late 80’s from an audio store that was going out of business.

The RS-5000’s had sealed bass that extended down into the 40’s (30’s in room) that always sounded better than it seemed like it should out of a cheap 10″ poly woofer. The EMIT tweeter was particularly impressive in how it could reproduce the sound of breaking glass – several times, while the TV was on, it fooled me into checking the windows in my apartment. The 3″ poly cone midrange was the weak link.

While I enjoyed my time (about 10 years) with the RS-5000’s, high on my wish list was always the Kappa series with the dome midranges and sleek cabinets (wide and shallow with big radiuses. When the InDIYana contest theme for 2016 was announced as “Widebodies”, the image of those Kappas immediately came to mind. The Indium 7 is a tribute to those.

Design Goals:
The goal is to create something with the basic form factor as the original Infinity Kappa series from the 1989-1991 time frame using similar, but modern, drivers. The target cost is $300 for drivers and crossovers to keep the project affordable.

Driver Selection:
Tweeter: The original Kappa series had a vertical planar tweeter that was relatively short. The BG Neo3PDR was essentially a better version, but is NLA. The other planars that PE carries are considerably longer than the original EMIT, which will negatively impact vertical dispersion. The later .1 versions of the Kappa used the EMIT-R, which was quite similar to the Beston RT-003C – so that is the tweeter of choice for this project.

Midrange: The Kappa series all had 3″ poly dome midranges. The Kappa 8 and 9 also included a larger “polygraph” midbass coupler – also a dome. The only dome midrange offerings at PE are currently 2″ – so that pretty much forces this project into a Kappa 7 clone with a 2″ dome midrange and a subsequent need to play the woofer up pretty high to cross to that dome. The 2″ dome options are the Dayton classic dome, Dayton RS dome, HiVi DMN-A, and the Morel MDM-55 (and the further upscale elite version). The MDM-55 is a known performer, but was ruled out in an effort to hold to a driver and crossover cost around $300. I’ve heard the RS dome a number of times, it has strengths and weaknesses, but I really didn’t think it would be a good fit for this project with its somewhat vintage theme. That leaves the HiVi and the Dayton Classic. I don’t recall seeing a project with the HiVi dome and am a little more intrigued by its potential than th e Dayton Classic. The DMN-A is used in an Italian open baffle hybrid speaker called the Ballerina, where it was crossed around 800 Hz and was favorably reviewed by 6 moons. I always take such reviews with a healthy dose of salt, but that at least gave me confidence that it could get to a viable crossover point. There are other reports that people had used these to replace Dynaudio domes with good results, so that gives me some further assurance that this will perform appropriately for this project. HiVi DMN-A it is…..

Woofer: Cost constraints along with the required crossover point around 800 Hz and a desire to have sealed bass with f3 below 50 Hz narrows the field. The crossover point suggests that a 10″ woofer would be a better solution than a 12. In order to fit into budget, the cost should be around $50 or less. Several Dayton drivers are good candidates: Classic, Aluminum, DVC. Of the three, the DVC is pretty smooth out to around 2kHz, has the right look, and has acceptable inductance when the coils are paralleled. So, the Dayton 10″ DVC is the choice. Even though it is marketed as a subwoofer, its specs suggest that it is really a woofer that happens to have dual voice coils.

Enclosure Design:
I really don’t have the tools or expertise to create the large roundovers used in the original Kappa series. My coworker and fellow speaker builder Scott P. (who goes by Lionheart on Techtalk) alerted me to Tapease in Wisconsin, who offers large wooden cylinders, half cylinders, and quarter cylinders. I chose 2″ MDF cabinet corners for all 4 corners to give a Kappa look and feel. The orignal Kappas had Oak sides and a black front, so I am going for an inverted look with an Oak Plywood baffle and black sides and back. The overall dimensions deviate somewhat from the original Kappa 7’s in order to comply with the Widebodies guidelines. Baffle width will be approximately 12″ and the side boards are just under 4″ wide, which gives overall width and depth of approximately 16″x8″ with the cabinet corners. The resulting asthetic effect is sort of a hybrid between the Kappa 7 and the larger 8 and 9. Height is about 3 9″, which is similar to the Kappa 7 and gives an internal volume around 50 liters, which the 10″ DVC likes.

Enclosure Assembly:
The midrange and tweeter have sealed backs, so they don’t require separate enclosures. The tweeter is also surface mount, so it doesn’t require a countersink. Therefore, the baffle is fairly simple to cut out. Using the 2″ cabinet corners does require some different construction techniques. I found the best method to be putting together the sides, front and back at the same time with the cabinet corners in place. Glue was applied to all joints except those touching the oak plywood baffle, which I wanted to keep removable. The assembly was “clamped” together using ratcheting tie straps. With the shell assembled, I added top and bottom end caps and then installed bracing made from 4″ wide 5/8″ thick particle board strips. The internal photo shows the bracing pattern. Threaded inserts were installed in the two cross braces in the front of the cabinet along with positions near the front corners in order to fasten the baffle. Weather stripping was used to ensure that the baffle sealed to the cabinet and to dampen any vibration.

Crossover Design:
The final crossover schematic is shown in the figures. The 10″ Dayton DVC really has smooth response out to 2kHz as the spec sheet indicates. I was able to get a smooth rolloff at about 700 Hz using a simple second order filter. The dome midrange matches up with the woofer using only a single cap. The crossover between the mid and tweeter is at around 5.5 kHz using third order filters The crossover includes a 2.2 ohm resistor before the midrange and a 12 ohm resistor before the tweeter to balance the sound pressure levels of the drivers. The resulting measured response is within about +/- 2 dB from the low frequency limit of my gated response measurement (about 300 Hz) to 20 kHz. Measured sensitivity is 86 dB with 2.83 V input at 1 meter. Off axis response is also smooth with no major discontinuities other than a narrow band dip around 6 kHz. In spite of the 4 ohm (with voice coils wired in parallel) subwoofer, impedance stays at or above 3.7 ohms throughout the audible frequency range, so it should not be as difficult a load for amplifiers as the big Kappas were.

Conclusion:
This project really exceeded expectations, both in terms of appearance and sound quality. The construction process using the cabinet corners was quite a bit different than anything I have attempted before, but the corners work well to provide a well-reinforced structure and create big roundovers that would be difficult to achieve by ordinary means. Before starting this project, I would not have guessed that the Dayton DVC sub would work well enough as a woofer to cross over to a 2″ dome midrange.

About the Designer:
Scott Sehlin lives in Bettendorf, Iowa with his wife and two sons. He is an Engineering Manager for a manufacturer of aerospace equipment and a member of the Parts Express Speaker Building Design Team.

Project Parts List

Designer:
Dan Neubecker (dlneubec)

Project Category:
Tower Speakers

Project Level:
Advanced

Project Time:
20+ Hours

Project Cost:
Over $1,000

Project Description:
The Scimitar’s are a state of the art, floor standing, passive 3-way speaker utilizing all top end drivers from Tang Band.

Design Goals:
Reference standard performance, including excellent balance top to bottom, flat power response, great off axis performance, low end flat to 20hz in room, with a wide, deep soundstage, capable of high spl with low distortion, all in a unique, attractive, but not too large aesthetic package. To combine some of the best drivers Tang Band has to offer in one speaker. A speaker that would not require additional subwoofers for HT. The use of drivers that could not be easily damaged if left uncovered.

Scimitars chamfer layout rear

Scimitars chamfer layout

Scimitars Cut Sheet .5in_1

Scimitars Cut Sheet .75in_1

Scimitars Cut Sheet .75in_2

Scimitars layout_1

Scimitars layout_2

Scimitars layout_3

Scimitars layout_4

Scimitars Overall_plan-notes

Driver Selection:
Subwoofer/Woofer: Dual, Tang Band W8-2022 8 ohm subwoofers, wired parallel, and implemented in a push-pull configuration, front and back. This RBM subwoofer is a very low distortion, flat cone subwoofer that has dual surrounds and cone surfaces, with an excellent frequency response all the way to around 1500Hz.

Midrange: Tang Band W4-1757SB 4” Aluminum Sandwich flat cone driver. This neodymium driver has an aluminum honeycomb sandwich construction, with a built in protective cover and boasts extremely wide off axis response. Measurements on and off axis sum to flat all the way out to about 8kHz. These drivers have a very detailed presentation.

Tweeter: Tang Band 25-193 1” Titanium Dome. This neodymium tweeter has a coated inverted dome and is also capable of extremely wide dispersion. Frequency response is only down about 4 decibels at 60º off axis at 10kHz, which is pretty amazing for any tweeter, much less a 1”. It is also a high sensitivity tweeter with an aluminum mesh cover for protection. A shorting ring in the gap results in low distortion.

Enclosure Design:
Considerable time and thought was invested in the enclosure design. All sides are tapered and non-parallel, which is intended to contribute to reduced standing waves, decreased diffraction and a non-box-like look. This made it very complex to design in cad as well as to construct. There are around 56 separate parts included in the entire box.

Subwoofer/woofer enclosure: A removable bottom panel was configured to allow access the woofer and mid crossover, plus to install or remove the inward facing rear subwoofer. The subwoofer box is approximately 80 liters and includes a rear facing slot port of 8.06 sq.in, 16” in length, with a predicted tuning of about 20.7Hz and an F3 0f 19.8Hz. In room measured response is flat to at least 20hz. The box sides are ¾” mdf reinforced with additional ¾” pieces and window-type bracing. In addition, 3/16” rubber flooring is glued to the interior sides of unsupported panels to further deaden enclosure walls. A single horizontal layer of 3.5” Ultratouch denim insulation is placed central to the enclosure, above the first window brace. Window bracing is made from ½” plywood and dado’d into the box sides.

The base was designed to hide the spikes used and to make it look like the speaker just barely touches a typical carpet, while still providing a stabilized base for the speaker.

The push-pull subwoofer configuration is said to reduce lower order distortion, though whether 2nd order or 3rd order seems up for debate, depending on who you are talking to.

Midrange enclosure: This enclosure has all tapered sides, tapering from front to rear where it is about 1” tall. There are five 1” diameter holes on the rear side. The box is heavily stuffed with a graduated and varied stuffing mix that includes a sandwich of Ultratouch insulation behind the driver, followed by a layer of 3” fiberglass insulation, followed by a thick layer or Dacron fiber. This configuration was the results of much testing of combinations and amounts to get as flat a frequency response at the rear output as possible over the bandwidth used. In practice, the idea is for the midrange enclosure to perform much like a sealed box, but with a tapered and heavily stuffed transmission line to reduce standing waves, yet allows a modicum of rear output for increased soundstage depth and potentially improved directivity match between midrange and tweeter. The rear output, however, is not substantial enough to restrict placement options as a full open back or baffle approach might.

In addition, the walls of the midrange enclosure uses a constrained layer construction with ¾” mdf on the outside, followed by a layer of 3/16” rubber material, followed by ¼” hardwood plywood, to ensure a very well damped enclosure. The top panel of the midrange enclosure is also removable and has a layer of 3/16” rubber material on top that sandwiches between the midrange and removable tweeter enclosure. The inside of the driver opening is scalloped to allow as much room for the driver to breathe as possible.

Tweeter enclosure: the tweeter enclosure is simply a dual walled mdf enclosure with a removable bottom panel. This allows access to the tweeter crossover, which is housed in this enclosure, rather than in the bass bin.

Enclosure Assembly:
This was a very complex enclosure to assemble and parts had to be cut and dry fit to ensure accuracy. Even though the 2d cad plans were as accurate and complete as I could make them, some reworking of parts were needed, either due to some unforeseen conflicts, or less than perfect angle cuts on the 4 outside tapered panels. Chamfers along the edges of the front and rear baffles were cut prior to assembly, using a table saw with a jog constructed to hold the panels at the proper angles. Rounding of the chamfers along the middle of the baffles were done by hand with a belt sander.

Construction adhesive was standard Titebond wood glue throughout. Body putty (bondo) was used in some places at panel interfaces, but later v-grooves were cut at these interfaces to seams from telegraphing through the painted finish and to compliment the overall aesthetic theme. The V-grooves at the panel interfaces and along the front center baffle were cut after enclosure assembly was complete.

Fiberglass resin was applied over the entire enclosure, both to make for a consistent surface upon which to apply paint, to treat raw mdf edges and inhibit seam telegraphing. This proved to be problematic in that the resin did not want to dry properly and some areas remained sticky to the touch, making it very difficult to sand, despite carefully following recommended hardener mix ratio and temperature recommendations. I’m not sure I can recommend that step unless you are already experienced and comfortable with this resin.

After sanding, several layers of primer, designed to cover fiberglass, were applied and sanded smooth. Once good, smooth coverage was reached, the preparation of each section departed. For the main box, I applied a couple layers of satin gray latex enamel paint with a super fine roller. The tweeter enclosure and the base of the speaker were done with black DuraTex, using a fine foam roller, followed by a chalkboard spray paint from Krylon to reduce sheen. The removable panel and slot port were also treated with black DuraTex, but then covered with a gloss claret red Rust-Oleum Painters Touch UltraCover 2X spray paint. Subtle hints of this claret red were also applied to the top of the main box, between it and the tweeter box, in the midrange box rear holes and also on secondary panels on the sides and front of the base.

Crossover Design:
Crossover points are around 320hz and 2.4 khz. All drivers are wired with standard polarity, except the rear subwoofer, which is wired in reverse polarity. However, since the rear woofer is mounted inward, the reverse polarity keeps its output in phase with the front subwoofer. The 2.4khz point was felt to be ideal to match directivity between midrange and tweeter to retain as flat a power response as possible. Inductors are all air-core and caps are all polypropylene. The total parts used in the crossover design are 13, however the actual number of components are higher, as multiple 47 uF caps were paralleled to reach the cap values specified in both the woofer and midrange circuits. Power response is very flat, with a slight slope downward as frequency increases. This was predicted by digital MLS design measurements and confirmed by measured RTA in room results, which also indicate low end extension flat to 20Hz. Impedance and impeda nce phase are fairly flat, with impedance not extending below 4 ohms at any point.

Tips & Tricks:
It pays to create a jig to cut baffle chamfers with a table saw.

Chamfers around the midrange and tweeter, as well as tapered sides, can substantially reduce edge diffraction and increase aesthetic variety.

Use non-parallel sides to reduce standing waves and multi-layer/constrained layer construction, in addition to substantial bracing, to address panel resonances. Also, it is always best to make unsupported panel sizes differ so that any resonances are spread out and not concentrated at a specific frequency.

Different types of stuffing seem better at attenuating different frequency response ranges and sometimes the ideal results may come from use of multiple materials.

I would avoid the use of fiberglass resin if I were to do it again, though that might be due to my lack of experience in using it.

I used a combination of threaded inserts, cap head screws, carriage bolts, etc. to allow the both the top panel of the midrange box and bottom panel of the tweeter box to be removable, as well as the entire tweeter box. The use of a rubber spacer between the mid and tweeter enclosure provides vibration isolation and functions as a constrained layer damping system for both panels when bolted together.

Conclusion:
The results of this effort have been very rewarding. It was a very difficult speaker to both design and build, though the painted finish was quite easy, excepting the issues I ran into with the use of fiberglass resin. It is definitely a project only for advanced woodworkers. The Scimitar’s are full range speakers that are very effective as both Home Theater mains without separate subwoofers or as part of a 2 channel music system. These Tang Band drivers are some of the best I’ve used in each category, and sound great together. The RBM subwoofers could be effective as woofers in a 2-way as well.

About the Designer:
Dan is a member of the Parts Express Speaker Design Team. He has been designing and building speakers for over 10 years and has designed and built and/or developed crossover designs for more than a dozen award winning speakers during that time. He brings to the hobby a love for both audio and woodworking.

Project Parts List

Designer:
Park

Project Category:
Tower Speakers

Project Level:
Beginner

Project Time:
8-20 Hours

Project Cost:
$100 – $500

Project Description:
This is a highly modified discarded Zen OB cabinet with a modified side fire 12 inch sub.

Design Goals:
I always liked the TB 1808 and love open baffle sound. To fill the low end, I knew I would need to add a sub of some sorts. You could include any of the easily accessible 12’s.

Driver Selection:
Tang Band 1808
GR Research 12, with PEQ 370 amplifier

Enclosure Design:
OB upper, with a sealed lower 1.75 cubic foot cabinet.

Enclosure Assembly:
Front baffle is 6/4s maple boards laminated together and screwed to the back box. The side fire is in a 3/4 mdf box with a 1.5 inch side baffle. The amp is cut in to the back of the lower chamber.

Crossover Design:
None, but I built modified amp/rca high pass filers specific to my amplifiers ohm rating.

Tips & Tricks:
Take your time.

Products Used:
Tang Band 1808 Part # 264-894
and 12 inch with plate amp

Conclusion:
Great combination of drivers with the ability through the plate amp to bring the lower woofer up to meet the ob full range driver.

About the Designer:
I get bored, love to build, then sell, then build something else..

Designer:
Park

Project Category:
Tower Speakers

Project Level:
Beginner

Project Time:
8-20 Hours

Project Cost:
$100 – $500

Project Description:
This is a highly modified discarded Zen OB cabinet with a modified side fire 12 inch sub.

Design Goals:
I always liked the TB 1808 and love open baffle sound. To fill the low end, I knew I would need to add a sub of some sorts. You could include any of the easily accessible 12’s.

Driver Selection:
Tang Band 1808
GR Research 12, with PEQ 370 amplifier

Products Used:
Tang Band 1808 Part # 264-894
and 12 inch with plate amp

Enclosure Design:
OB upper, with a sealed lower 1.75 cubic foot cabinet.

Enclosure Assembly:
Front baffle is 6/4s maple boards laminated together and screwed to the back box. The side fire is in a 3/4 mdf box with a 1.5 inch side baffle. The amp is cut in to the back of the lower chamber.

Crossover Design:
None, but I built modified amp/rca high pass filers specific to my amplifiers ohm rating.

Tips & Tricks:
Take your time.

Conclusion:
Great combination of drivers with the ability through the plate amp to bring the lower woofer up to meet the ob full range driver.

About the Designer:
I get bored, love to build, then sell, then build something else..

Designer:
Hong Nguyen

Project Category:
Freestyle Speakers

Project Level:
Advanced

Project Time:
30-50 Hours

Project Cost:
Under $500-$1000

Project Description:
This is a 2-way design using a 12 inch pro woofer coupled with a compression driver in waveguide. The speakers are designed to be on the floor, and tilted towards the listener, not unlike a stage monitor.

Design Goals:
My goal is to design a high sensitivity speaker that can be used for many different purposes, to listen to music using low powered tube amplifiers, or for karaoke or PA purposes. The cabinet can be propped on stand, or can be left on the floor. A typical 5′-9″ individual standing 10 feet away would perfectly face the speaker baffle on axis.

Driver Selection:
I selected the Eminence Deltalite II 12″ Neo woofer due to its light weight and relatively small box requirement. The fact that its frequency response can extend to 3KHz is also important in a waveguide design. For the tweeter, I chose the Eminence PSD 2013 compression driver due to its ability to cross fairly low and relatively low price. For the waveguide, the SEOS-12 was used due to the fact that it allows low crossover points with minimal distortion, and is generally well reviewed by DIYers.

Enclosure Design:
The enclosure volume is 3.3cu.ft with a F3 of 50Hz. The vent is 2″ high by 13.5″ wide, and 6.25″ deep. Due to the unusual shape of the cabinet, I modeled the box first in Bassbox to determine the volume, then I used Sketchup to model the shape of the box based on this volume. I then “broke” the box apart to determine the shapes, dimensions and angles of the different panels.

Enclosure Assembly:
Cutting the panels was time consuming due to the fact that the table saw blade had to be adjusted according to the angle of the panel. Once this was done, putting the box together was straight forward. Sketchup was accurate to the point that all pieces fit together with very minor adjustments.

Crossover Design:
The crossover point was around 1,500Hz, which was the minimum frequency recommended by the tweeter’s manufacturer. Both the woofer and the compression driver behaved extremely well, with the woofer requiring just three components, and the CD another three with a RLC notch filter to achieve steep 4th order slopes. Phase tracking was relatively good, given the deep z offset between the woofer and the CD.

Tips & Tricks:
Sketchup or a similar 3D application will make designing unusually shaped speakers more practical, and also helps maximize panel cuts to avoid wastage.

Conclusion:
This project is my first foray into the world of pro woofers, one that validates what all of you have been discussing and writing about these drivers. With certain tracks, these speakers give the music a definite “live” quality as if one was standing close to the stage. If you like to sing, these high sensitivity drivers will make it effortless to hit your notes. The simplicity and low cost of the crossover components are also a big plus.

About the Designer:
Hong Nguyen is a healthcare professional specializing in the development and management of ambulatory surgery centers, and a member of the Speaker Building Design Team.

Parts Used:

Designer:
Park

Project Category:
Tower Speakers

Project Level:
Intermediate

Project Time:
20+ Hours

Project Cost:
$100 – $500

Project Description:
This is a project propagate with the help of Dave over at Planet 10 Audio ( Canada ) I had been making some of his smaller single driver speakers and wanted to use the Tang Band 1808 driver in one. He put together the following for me.

Design Goals:
Single driver, Tang Band 1808 with a tower speaker feel and great looks

Driver Selection:
Tang Ban 1808
You are unable to change drivers to another 8 inch unless the specs are the same do to the porting on the sides

Enclosure Design:
Full tower with side ports/vents to help out the bottom end.

Enclosure Assembly:
Left over wood from the shop, walnut, baltic birch, maple, and cherry. I was not worried about the different boards pulling apart because he will be in a AC/Heated room with low humidity.

Crossover Design:
None, no bsc, nothing.

Conclusion:
Great looking speaker and I have always loved the driver. Spectacular top end and midrange, but can get away from you with too much power. I think I would like to add the three 8 inch subs to this to really make it a full range speaker.

About the Designer:
Build, build some more, have fun….

Parts Used:
Tang Ban 1808
You are unable to change drivers to another 8 inch unless the specs are the same do to the porting on the sides

Designer:
Ken Temple

Project Category:
Home Theater

Project Level:
Intermediate

Project Time:
8-20 Hours

Project Cost:
$100 – $500

Project Description:
Rebuild of a Thiel MCS 1 Speaker Cabinet into a Frankenstein Monster

Design Goals:
Rebuild the entire speaker into a Phenomenal Center Channel Speaker for a Home Theater.
Refinish the entire cabinet & add new & better speakers & tweeter.

Driver Selection:
(1) Dynavox TD2801XL 1-1/8″ Silk Dome Tweeter part # (275-200)

(2) Peerless 830946 6-1/2″ Paper Cone Woofer Speaker 4 Ohm part # (264-1148)

(1) Dayton Audio XO2W-2K 2-Way Speaker Crossover part # (260-140)

Enclosure Design:
Thiel MCS 1 Center Channel / Tower

Enclosure Assembly:
Thiel MCS 1 Center Channel

Crossover Design:
Dayton Audio XO2W-2K 2-Way Speaker Crossover

Conclusion:
One seriously phenomenal sounding Center Channel

About the Designer:
I am the welding & fabricating supervisor at Sound Anchors in Palm Bay, Fl.
Ive been into audio since about 15yrs of age.
Originally from Louisiana.
Ex Navy of 8.5yrs

Project Parts List

Designer:
Jackson Audio

Project Category:
Subwoofers

Project Level:
Intermediate

Project Time:
20+ Hours

Project Cost:
$500 – $1,000

Project Description:
I built a multipurpose subwoofer cabinet to both use at parties and at home.

Design Goals:
I wanted to both follow the recommended cabinet design, and create a unobtrusive but powerful subwoofer to compliment any sound system.

Driver Selection:
The only driver is a Dayton Ultimax 15″ subwoofer driver (295-514)

Enclosure Design:
The enclosure was designed to comply with the recommended cabinet specifications, which are as follows:

6.0 cubic ft. net internal with two 4″ diameter by 26″ long flared ports.

I designed the cabinet to have internal dimensions of 18″ x 24″ by 28″, for a total internal volume of 7 cubic ft., with drivers, ports, and braces, it would hopefully be closer to 6 cubic feet.

The cabinet was made with 3/4 in. MDF and has 2 ports, 26″ long that have flares on both ends and bend in the middle to accommodate the cabinet’s 24″ depth.

Enclosure Assembly:
I built the cabinet out of 3/4″ MDF, held together using wood glue and predrilled screws. The ports are held in with more pieces of MDF, which are also glued in. The cabinet is finished with 2 coats of Duratex for a durable, rough finish.

Conclusion:
Next time, I hope to use a router table to avoid redoing lots of my cuts to make everything fit together. I am very impressed with the power of both the Ultimax and the Behringer amplifier.

About the Designer:
I started designing and building speakers around 2 years ago. I have learned a lot from Parts Express that has improved my builds, but I hope to continue building speakers.

Project Parts List