Chipamp done!

[FenderBender11]

Took me an entire year to complete this...It was my first amp. One thing I learned: Mocking it up is one thing, getting it all to fit in an enclosure and wiring it is another.

Another thing: Know where to stop! Don't just keep adding things like I did. At first I was going to just have a stereo amp, then I decided it would be nice to have a subwoofer output, which then brought about the necessity of an active crossover..and then I thought it would be nice to have a headphone output. Which is why this got delayed.

Well it uses 2x LM3886TFs for left and right channels and then a paralleled LM4780 + active crossover for the subwoofer. Non-inverting op amp in the corner (cmoy) for headphone amplification. Heatsinks are computer-type heatpipe heatsinks.

Film caps are all Wima. Electrolytics are mostly Panasonic FM or FC. Power supply caps are either Panasonic, Nichicon or Nippon Chemicon. Metal film resistors where applicable.Switches are Nikkai (NKK). RCA connectors are Neutrik. Banana jacks are Parts Express gold plated. Most of the low voltage signal is run on Belden shielded wire, though I ran out and simply used some twisted two wire stuff. (Shh!!).

Transformesr are 250VA 25V+25V and a 6VCT 1A for running peripherals and fans. The amp is actively cooled by two 12VDC vans running on about 7VDC, so it's pretty quiet and stays cool. Intake from under the right-most heatsink and exhaust out the one on the left.

Chassis is built by me. It has 1/2" oak top and bottom and 1/4" poplar sides. Metal enclosure would have cut down on noise, but hey, it looks pretty cool. I actually thinking about painting some racing stripes right down the middle for some added kick.

So here it is. I only have 3 pics, but that's the jist of it.

PS. I like hot glue. Don't hate!

[Super Josh]

Nice use of heat-pipes Were they expensive?


SJ

[noddy55]

Hi,

Good Job! I can see the amount of efforts you put into it. Nice and elegant heatsinks. Exteriors would look more elegant, if you can varnish the box and What about some metal knobs matched to the varnish finish box?

Thanks!

[FenderBender11]

Originally Posted by noddy55

Hi,

Good Job! I can see the amount of efforts you put into it. Nice and elegant heatsinks. Exteriors would look more elegant, if you can varnish the box and What about some metal knobs matched to the varnish finish box?

Thanks!

Thanks.

The box does have a few coats of polyurethane. The picture looks a bit bad.

And the knobs. Those are some cheap $0.69 Neutrik knobs, yeah I know. I was running out of cash so I couldn't spend $5 on a knob. I might scour ebay and see if I can find anything nice...the current knobs do have a nice soft touch to them though.

[ptempel]

Well done. Your project is much more ambitious than mine was. Am almost ashamed to say that I built my amp using the classdaudio.com kit. Still have to drill out a metal chassis, but was much less work than you did. Now you can tackle a preamp (line stage) project! I just received the lightspeed attenuator full kit so am looking forward to building it.

[FenderBender11]

Originally Posted by Super Josh

Nice use of heat-pipes Were they expensive?


SJ

I believe the total cost for all of the heatsinks was around $40. I guess that's expensive but it does allow me to use smaller heatsinks.

[overtheairbroadcast]

Nice layout -- did you sketch it up or how did you go about it?

[FenderBender11]

Originally Posted by overtheairbroadcast

Nice layout -- did you sketch it up or how did you go about it?

Thanks. No I just played around with all of the parts for a while. I think I have pictures. The initial layout looks nothing like the final one.

[geraldfryjr]

Very Cool !!

I have been wanting to try using CPU heatsinks as well.

Can you tell me which ones you used and may be some temps as well as I see that you are not using a fan.

I have some LM4780's that I want to use in a large paralleled chipamp.

CPU coolers seem to be the most cost effective method to use these days.
Especially when you can pick up some old P4 ones relatively cheap as well.

And also where did you find them as $40 for all of them as you said is a very good deal.

I am thinking about a few Ximatec's from Newegg but if you know were they can be gotten for cheaper it would be much appreciated to know where!

Thanks !!

jer

[johnr66]

I see a fan to the left, but where are the inlet ports?