Parts-bin SS build

[MereTenacity]

Interested in a nice clean SS amp using some stuff I had around. I've scrapped a few consumer-fi chassis Denon, Onyko, Yamaha, etc. as well as the odd psu, synth, and whatnot and figured i'd try a bit bin project.

I have these transistors/fets already scavenged, and more hiding on boards:
5x a1695
5x c4468
5x c3421
5x c5171
5x a1930

STPS3045CW
STPS30H100CW
PQ05RD11
29M33
KA7085A
E13009F
78M12A
LA4705N
RBV-602
RBV-402
2x 78M05A
2x GBU-608
2x K2611
2x TIP117
2x LT6217
4X 0609A

And Mountains of more common components.
Buckets of caps, Piles of transformers, etc.

Curious if anyone has an existing (or easily adaptable) amp design that could use these. I'm going for stereo hi-fi, but even a good mono instrument amp design could be fun. I don't want to fiddle endlessly, just build a nice functional power amp.

[gmphadte]

The most important parts are the complementary power transistors and the most costly are the power transformers. As far as the parts list goes, there is no usable parts for a power amp. Best is now list your power transformer secondary voltages and u can find out which amp u can construct. Other small parts cost less.

Gajanan Phadte

[MereTenacity]

Considering the fact that most of those came directly from the audio circuts of intergrated amps i think you are absolutely incorrect. Please be unhelpful somewhere else.

[gmphadte]

Slip of memory, I am getting old.

Gajanan Phadte

[djk]

"Considering the fact that most of those came directly from the audio circuts of intergrated amps i think you are absolutely incorrect. Please be unhelpful somewhere else. "

The active devices are the least expensive part of an amplifier, I would never salvage any transistor (other than Yamaha depletion FETs or similar).

Salvage heatsinks?

Yes.

Salvage transformers?

Yes.

Salvage transistors?

NO.

[Fast Eddie D]

If you have transformers and heatsinks, you can buy a chipamp kit from SleazeBay and be up and rolling for cheap.

I've built a few amps from virtually 100% salvage parts; including diodes, transistors, chip amps, even capacitors. I did it as an exercise. I am actually using one of my "zero budget" amps for my second TV. But I realise that it could go south at any time. It all depends on what you want out of it. I did it to come back up to speed after not being involved in the hobby for around 20 years.

Old transfomers are good as gold. Heat sinks are great too. Old chassis can be re-bent into new custom chassis. You can get a "mini-bender" from autobody supply sources, or you can make one yourself. It's only limited by your imagination and ambition.

[Fast Eddie D]

18" Mighty Mini Bender Brake

I own one of these and it's the perfect size for fabbing up enclosures.

[MereTenacity]

Originally Posted by djk

The active devices are the least expensive part of an amplifier, I would never salvage any transistor (other than Yamaha depletion FETs or similar).

Point taken. Sorry for the snarky reply guys. Must have been low on caffeine.

I just figured a parts-bin build would be cheap and fun.

Thanks for setting me straight. Transistors are not terribly pricey, so that makes sense.

Now I'm curious how hard it would be to build a web search engine where you list your components on hand, and it would spit out a list of projects than can be built from a database of schematics. I think parsing the schematics would be the difficult part.

I actually have TONS of chassis's thanks to being an IT guy by trade. I get about 2 a month that would only need new faceplates and already have nice fused and filtered IEC C13/14 plugs chassis-mounted.

Guess I'll prep a chassis and go fishing for a design I like. I'm so used to re-using tubes, i figured it would follow that transistors would be similar.

[Fast Eddie D]

Originally Posted by MereTenacity

I just figured a parts-bin build would be cheap and fun.

It is. My parts bin amp is still in service three years later. It cost me $20, mostly for capacitors.

You need to have realistic expectations is all. It's a great way to learn and keep busy, as well as proofing designs. If you fry up a couple of 30 year old transistors, who cares?

What I got the most satisfaction from is that my creations worked so much better than the units I stripped for parts.

Now I'm curious how hard it would be to build a web search engine where you list your components on hand, and it would spit out a list of projects than can be built from a database of schematics. I think parsing the schematics would be the difficult part.

I just sort some parts out of the bin and design a circuit to work with them. It's just "parts bin engineering."

[MereTenacity]

If I was a better engineer, I wouldn't be asking for projects that fit my parts, I'd design one myself. I'm still at the understand the basics enough to mod things stage, and am trying to progress toward designing my own. Other than a few stomp-boxes of primitive (but effective) design, a few passive crossovers, and a dodgy guitar amp build from old radio tubes that kinda works (was my fist attempt, years ago) I've really not built many audio circuits from scratch.

I'm not a noob either, I've built about 4 analog synths, and thats where most of my audio-engineering know-how comes from. I can design a resonant LP cutoff filter with my eyes closed, nevermind that it will look almost exactly like a moog circuit, but why stray too far from glory? I'm just inexperienced enough to be annoying to the true engineers here it seems. :-D

Maybe this thread should be re-incarnated as a "Where to salvage awesome parts thread" as I seem to have a very firm grasp on that. If only I could find a good source for 10-100uf 400v caps... I have piles of 200v caps rated 200uf to 1600uf from power supplies that would love to find a home.