Seeing as I really don't have too much to contribute elsewhere (many of you guys have a much more in-depth understanding of this hobby than I do), I figured I'd throw in the project I'm currently working on.
Being in the northeast without a garage, its wayyyy too cold to work on the car, so we turn our sight indoors. I've been wanting to upgrade my HT for a while now. The receiver does everything I could need currently and the new TV handles all the video without issue, but I could go for a matched set of speakers. The current plan was to go with a Triune 5.1 setup, but my receiver is not capable of delivering 4ohms continuously. I know I could go to the 8ohm version, TriTrix, but what if I want to upgrade again later? So in comes the project.
I started over at DIYAudio in the class D section. Aparently there was a company selling 4ch amp modules on eBay for $50. Figured it was worth a shot. So how about a chassis? back to eBay, awesome all aluminum chassis for $100 shipped (steel chassis available for under $50). RCA's and binding posts? ebay again, $10 for 10 rca's and $10 for a set of 4 binding posts. Switchmode power supply? guess where, eBay again.
So time for me to show some pics. Its not done, so bear with me, but everyone loves progress pics
this is the chassis as it arrived. from everything i could find, it was built better and cheaper than many of the other available options.
yes, 1/4" thick front panel. this thing looks good.
10 minutes later (I don't waste any time on this), the case all together. All the necessary hardware was included and all the holes had pressed in nuts, so no worries of stripped aluminum.
Here is the layout I'm going with, cept the PS will be on the opposite side. Nothing's bolted down, just checking for room.
the in's and out's. awesome quality for the money, quickly received (got them in 2days from Cali to Mass). I made an oops and ordered only half as many binding posts as i needed. more on the way.
So here is where I stand thus far. Beeing sick and working long hours makes progress slow, but I did start drilling out the rear panel for the hardware. Need to get some more screws, etc for mounting the boards, but otherwise everything is here. Oh, need to get a decent IEC socket, something thats maybe fused and filter, but who knows. Still trying to figure out how to get a Bulgin vandal switch (check google, you'll like what you see) to work as a power switch, but thats something for later.
i did a test run with both amps just to make sure everything was working. unfortunately, one channel gave up the smoke ( ), but the other 7 work fine. speaking with the seller currently on their warranty policy. they seem to do pretty well, but there is a slight bit of noise if you put your ear up to the speaker. some people have done some mods to be rid of this noise, so i'm looking into that as soon as i get the thing together and at least do some quick listening. i understand $50 isnt going to buy the best amp in the world, but for my uses (mainly home theater and gaming) it should work well.
yessir. the SMPS I grabbed was their 24v, 14.6a piece. maybe not optimal of all channels are being driven, but chances of all 8 going full tilt (which wont be anytime soon as it will only be powering 5 speakers) is slim enough that it should do for now.
Kick ass project man. Keep it up and learn all you can.
I did a similar project a few years back. Bought up a dead ADCOM GFA-555II on ebay for around $80 shipped. Outputs were fried but the linear supply was good. I originally just bought it for the sexy chassis but ended up using the supply too. It is now a subamp based around a Tripath 1KW (bridged) amp module. Pounds the bejeezus out of two Mass 2012 subs in my living room. I've never got around to measuring true output but my best estimate it will deliver a clean 800W into 4ohm.
I did a writeup on this project a while ago. However, can't find the log book for the life of me.
Alpine, Zapco, Scanspeak, Image Dynamics, Critical Mass
Life lesson #1) En boca cerradas no entra moscas! (loose translation: sometimes it is best to keep your fuggin mouth shut and listen)