Yup, the Egad will give way to the Egad mkII 
Nothing bad with the amp itself, in fact, it's working good and sounding wonderfully, but a few things keep irritating me:
- The heatsinking is too inneficient for my taste. At 70-75° each, the bjt's are well within their limits, but this is too hot for touching more than a few seconds after an hour or so.
- Noise. I might be a maniac , but there's a tiny hum listenable if you're near the speakers, and this is mainly to my poor grounding. The capx psu works like a charm, but's no good if you're picking hum with the rest of the wiring
- I'd like to redo the boards (psu, protection/vumeter and amps) on pcb, perhaps even hand-sketched. Have most on Veroboard and it'll get bitchy if i ever have to replace something. Besides, i'd love a smoother layout.
I really like the wood case, but well, a price must be paid. So, i was thinking something in the line of an Aleph case, you know, "block with sink sides", with two small wood "windows" on front and back to hold conectors, leds and stuff. I want to spend little, so, what about buying Al profiles, like the ones used in construction, and building the panels with them? L shaped, for example, is very cheap ($5-6 the kg.) and someplaces it's even anodized. Think of this
LLLLLLLLLLLLLL <= L profiles, bolted
=========== <= couple of large Cu or Al strips holding it in place (and a transistor per side).
I know someone has tried something like this and posted about it here, but i just can't find it. In theory this would work ok if everything's tight and i get the right shapes (gotta do some shopping). Comments?
Nothing bad with the amp itself, in fact, it's working good and sounding wonderfully, but a few things keep irritating me:- The heatsinking is too inneficient for my taste. At 70-75° each, the bjt's are well within their limits, but this is too hot for touching more than a few seconds after an hour or so.
- Noise. I might be a maniac
, but there's a tiny hum listenable if you're near the speakers, and this is mainly to my poor grounding. The capx psu works like a charm, but's no good if you're picking hum with the rest of the wiring- I'd like to redo the boards (psu, protection/vumeter and amps) on pcb, perhaps even hand-sketched. Have most on Veroboard and it'll get bitchy if i ever have to replace something. Besides, i'd love a smoother layout.
I really like the wood case, but well, a price must be paid. So, i was thinking something in the line of an Aleph case, you know, "block with sink sides", with two small wood "windows" on front and back to hold conectors, leds and stuff. I want to spend little, so, what about buying Al profiles, like the ones used in construction, and building the panels with them? L shaped, for example, is very cheap ($5-6 the kg.) and someplaces it's even anodized. Think of this
LLLLLLLLLLLLLL <= L profiles, bolted
=========== <= couple of large Cu or Al strips holding it in place (and a transistor per side).
I know someone has tried something like this and posted about it here, but i just can't find it. In theory this would work ok if everything's tight and i get the right shapes (gotta do some shopping). Comments?
DIY heatsink
This site might be what you are looking for with regard to a DIY heatsink.
http://www.home.earthlink.net/~lotusblossom/index.html
DocP
This site might be what you are looking for with regard to a DIY heatsink.
http://www.home.earthlink.net/~lotusblossom/index.html
DocP
Yeah, i know that one. My idea is similar, but with the fins attached to a heat transfering strip instead of making the whole thing intercalating sheets. Using the "approximate" formula for bare Al shown there throws that with 10 or 12 25cm long fins per side (5cm deep each) i'm below 1°C/W. If it works, i'd be happy.
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