Like most of my ideas, I think of them when I'm desperately attempting to fall asleep. One night in July 2003, instead of sleeping, I was thinking about how I could use L-brackets to construct nice wall mounted speaker holders. All I needed were the speakers, and the L-Brackets, and a bunch of other things.
Instead of trying to sleep more, I started researching some small DIY speaker designs on the internet. Then I remembered seeing John's Audio Project website, where he had posted a Notch Filter and a few Designs using a little 3" Tang-Band full range speaker, which several people have claimed to sound pretty amazing. So, I went ahead and ordered 3 of these speakers, the Tang Band W3871S drivers from Creative Sound Solutions in BC. They shipped them out COD, perfect.
I had a bunch of MDF wood left over from my last speaker project and such. I ordered the neceessary stuff from Parts Express to be able to finish the speakers (crossover components, binding posts, etc). I also added a few things like audio cables, stuff I needed to fix my headphones and a few parts I needed to update my main speakers' crossover design.
Since I was building 5.1 speakers for my bedroom, I obviously needed something to take advantage of it. So, I ordered a new Soundblaster Audigy 2 24bit 5.1 sound card. For good measure, I also threw in an LG DVD ROM drive. Both of these I ordered through canadacomputers.com. Over a week went by without me receiving my shipment from them, so I called them and they admitted that they lost my order. So the rep told me he'd ship what I wanted out right away. Sure enough, the soundcard and the DVD drive arrived at my door the next day! Bam!
Next was the reqired 10 trips to the Building Box to get all sorts of little things that I kept overlooking. I think I actually rode my bike there around 4 times to pick up little things. The first was screws to hold the drivers in, L-brackets. Then I went back to get wall anchors and such. Then I got speaker wire and veneer. etc.
I had decided on building two of John's Smallest Enclosures for the driver as rear speakers, and one of John's Medium Enclosure to use as the center channel speaker. Since I intended on tipping this design on it's side to lay ontop of my monitor, I moved the driver to be in the center and changed it's height (now width) so it would be exactly as wide as my monitor.
One night around 4AM I brought all the scrap wood upstairs and started measuring it. I had a few extra baffles from the towers I made last time, and I managed to adjust the dimensions and construction of the cabinets so I only have to chop up the scrap MDF in the right lengths and only rip one of the scrap boards to a different width. The reason I did this is that this project was the first time that I ever really used the new table saw that I bought for anything that had to be accurate, and I didn't trust my ripping skills. It turned out that I could rip boards pretty well even on the fairly small table saw. Accuracy of all the cuts was within 1/16th of an inch, which is good I guess, but not as accurate as I would like to get for easy construction.
I practiced using the router to make the recessed driver cutouts a few times, and finally perfected it. The 3 holes in the speaker baffles turned out perfectly. Miles better than the tower speakers I made last year, whose holes are maybe 3mm off in some places. Since these drivers are only about 3" in diameter, being 3mm off would result in a very noticeable flaw, so I'm very happy with the results!! After the boards were cut and cleaned, I started gluing them together. Fortunately, I had a few extra clamps that I borrowed to use to clamp my guitar back together after it broke a few days earlier. By the time the cabinets were clamped and drying, I realized that these speakers are going to be a lot heavier than I anticipated and the little L-Brackets I envisioned holding these speakers a few feet right above my head while I sleep weren't going to cut it. I kept picturing one of these speakers falling off the wall and crashing down on my head while I sleep. My parents wouldn't even notice for a few days, because they would assume that I'm sleeping. I didn't want that, so I went back to the building box to pick up some big-ass shelf brackets rated at 80LBs. I also picked up some bigger screws to mount these right into a stud. Speaking about studs, while paying for this stuff, the really hot cashier at The Building Box pretended that one of the items wouldn't scan, just so she could flirt with me for longer while she waited for her manager. What can I say? Chicks dig unemployed guys who rode their bicycles to the hardware store at 7PM just after waking up to buy $3 worth of stuff on their interac cards.
Next step was contact cementing the wood veneer on. Just like last year's speaker project, I used birch veneer because I love how the finish turned out on the other ones. So, I veneered the speakers in a few hours one day. My veneering skills have also improved and I only made a few small mistakes. Then I started applying the same polyurethane I applied on the other speakers, hoping that they would match exactly. I was totally wrong. The veneer was totally different and didn't come close to matching at all. It was a lot lighter coloured, and didn't have hardly any flame to it at all. Oh well, I guess birch varies a lot from tree to tree.
Next step was to make the crossovers and secure them, and mount the drivers themselves. Done and done within a matter of an hour! I also included in the crossover a 100Hz highpass filter, which filters out any frequencies lower than 100Hz (where the bass really lives). The reason for that is so that loud bass notes don't distort or damage these little 3" drivers. This is where a subwoofer would kick in anyways, so it's not a problem. I didnt' build a subwoofer, which means my setup is actually a 5.0 setup since my main towers can handle any bass frequencies just fine. Eventually if I have cash, a nice subwoofer wouldn't be bad to build. Just to make sure bass can really be felt during movies and videogames.
By this time it was about 5AM and my parents were well asleep. I brought the two rear speakers upstairs and unplugged my main towers and plugged these two little things in and took a nice listen to Led Zeppelin I. Obviously a bit of bass was missing, since these are only 3" drivers. You can still hear John Paul Jones just fine, but you can't feel the bass notes, which was a good thing since my parents were sleeping anyways. The clarity of these speakers were very good throughout the whole vocal range I noticed. Imaging was very good, even at fairly low parents sleeping volume. I do like the idea of having a single driver in a speaker, since there is not transition between what is being played by the woofer and what is being played by the tweeter. Everything these speakers played had the exact same characteristic, regardless of frequency. I think that's the main appeal of full range drivers, I'm not sure though. The highs were a bit fuzzy or something I did notice once I got to crank them the next day. The speakers also can't be driven too hard, since they are only 15W max but I think they go as loud as you'd need them.
Before the project is finished, I also updated last years towers with a new crossover and some new wiring. I also added some nice connectors to the drivers themselves as well as a big piece of carpet (which I had to make another trip to The Building Box to get) behind where the drivers sit. I also replaced the cord on my headphones and did a few other random upgrades while I had the tools out.
The Soundblaster Audigy 2 is definately a good soundcard, especially for the $100CDN I paid for it at this time. The setup panel is quite good, and lets me redirect all the subwoofer frequencies to my two main speakers. I can also calibrate them, and change levels on each speaker to make sure everything is even. The EAX in videogames is quite good as well, and it's very neat being able to locate gunshots and various other sounds more accurately based on sound. All in all, this whole project was definately worth while even though the speaker construction seemed to be a lot more work than I first anticipated.
Home Theatre Speaker Project Budget [in CDN funds]
* not part of the speakers themselves
Creative Sound Solutions
(3) Tangband W3871S 3" Full Range Drivers - $68
Parts Express
(3) 100uF 100V Non-Polarized Capacitor - $7
(3) Dayton 3.3uF 250V Polypropylene Capacitor - $7
(3) Dayton .01uF 400V By-Pass Capacitor - $2
(3) .7mH Air Core Inductor - $14
(3) Dayton 7 OHM 10W Non Inductive Resistor - $5
(3) Gold Binding Post Pair - $20
(3) 3 Pair Gold Disconnects - $4
(1) 36" Speaker Sealing Caulk - $1
* (3) Portable CD Cable 5' 3.5mm stereo - $6
* (1) 3.5mm Gold Plated Stereo Extension - $4
* (4) 4OHM 10 W Resistor - $1
* (2) 20OHM 20W Resistor - $1
Building Box
12"x99" birch Veneer - $16
Contact Cement - $5
Screws/brackets/Anchors - $8
* 12M 16GA Speaker Wire - $10
* Carpet Remnant - $9
Canada Computers
* Soundblaster Audigy 2 OEM - $102
* LG 16X DVDROM OEM - $47
TOTAL: $180 (with 15% tax)
*GRAND TOTAL: $387 (with 15% tax)
Now, here's a boat-load of pictures from the construction of the speakers all the way to the final project!
