Sometime in the dim past I bought a pair of Audimation CPA 1 amps. Never heard of them? Not surprising, no one else has either, when you google them my own question on Reddit asking if anyone had heard of them comes up first. Anyway I bought these so long ago I forgot I had them until I had to move! These are monoblocks, sturdy little buggers at about 20 lbs each.
I've been using them on my bench doing speaker measurements for the last decade or so but they're getting kind of flaky, sometimes there's a big offset on the input, other times the bias is way off, typical stuff for old amps. So thinking I could repair them I took the cover off, and luckily for me there was a schematic inside. It turns out they're a pretty basic quasi complementary design, not really worth spending much to fix.
So then I thought I could use the chassis, heat sink and transformer to make something more up to date. The biggest problem I see is that the 2 output TO-3 transistors are on opposite sides of the chassis which means I'm looking at pretty long leads for at least one of the transistors.
Anybody got any ideas on a good use for these amps? I'm open to suggestion.
I've been using them on my bench doing speaker measurements for the last decade or so but they're getting kind of flaky, sometimes there's a big offset on the input, other times the bias is way off, typical stuff for old amps. So thinking I could repair them I took the cover off, and luckily for me there was a schematic inside. It turns out they're a pretty basic quasi complementary design, not really worth spending much to fix.
So then I thought I could use the chassis, heat sink and transformer to make something more up to date. The biggest problem I see is that the 2 output TO-3 transistors are on opposite sides of the chassis which means I'm looking at pretty long leads for at least one of the transistors.
Anybody got any ideas on a good use for these amps? I'm open to suggestion.
Wow that is really a tight space. Maybe just upgrade what you can for the amp as is. Very nice chassis BTW. Looks to be heavy duty.
A strange configuration with R117 C112 & R120 and quite old with these blue capacitors ( phillips 1980 ?? or so )
neutralisation R102 C103 C104 and feedback with C115 .... and bootstrap on the upper side ... some facy work ...