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My Yamaha M70 amp stopped working and the protection light is on. I'm good with electrical on cars, so I wanna refurbish and upfit it (3 pin grounded power socket instead of 2 pin hardwire, banana plug socketsto replace the twist speaker terminals).
How do I know what to replace?
Should I just buy a complete refurb kit for $200 and replace everything?
Showing all 23 replies.
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Last questions:
Some company makes plug and play banana plug retrofits panels for $50 but they're going to take weeks to get here from Germany.
Are there just cheap panel mount banana sockets I could get 8 of to replace these twist locks?
Should I put a screw mount IEC C14 power socket (PC power cord socket) on here or would something else be more elegant?
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>>2991707
>grounded
NGMI
It's not grounded for a reason.
>banana plug
If you keep unplugging these speakers of then than sure, otherwise screw terminal is fine.
The protection light means impedance is too low on amp out. Test it with no speakers, or different ones.
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>>2991707
>I'm good with electrical on cars,
forget about it, if you were good with electrical on electronics or even just houses, sure have a go at it, amplifiers aren't that complex
but car electrics are just OBD scanners and fuckhuge connectors
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>>2991824
I already have a class D and this is definitely better, of only for volume and aesthetics, but I honestly think it sounds slightly better too.
I have turbo pleb ears tho and can barely tell the difference between most equipment, so it doesn't matter.
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>>2991707
>I'm good with electrical on cars, so I wanna
Vintage audio that you care about having working again is not the best thing for your first serious repair project. It is one thing to make nice neat solder joints on a kit, which is also something you don't learn on cars, and another to desolder parts on a shitty PCB with a decade of residue on the solder joints without trashing stuff up.
>How do I know what to replace?
There's the rub.
>Should I just buy a complete refurb kit for $200 and replace everything?
Wouldn't it be something if you do all that and it never works again. Get it working first.
>>2991709
>I also reqd that I should replace the speaker relay with new Omron G2R-2 relays, is that necessary?
Oh ffs. No. Relay failures in consumer electronics are really rare. The relay in there is probably good for 100,000 cycles or more. There might be some audiophool reason people do that. Don't fix what's not broken.
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>>2991711
>Some company makes plug and play banana plug retrofits panels for $50 but they're going to take weeks to get here from Germany.
Are there just cheap panel mount banana sockets I could get 8 of to replace these twist locks?
Don't fix what's not broken. Those twist locks have some charm, anyway. And good banana sockets will run you a fair fraction of that $50.
>Should I put a screw mount IEC C14 power socket (PC power cord socket) on here or would something else be more elegant?
That Heyco strain relief is plenty elegant.
>>2991742
>Check your DC voltages, that's most likely problem, followed by testing your power transistors.
Yes. I would have done that in the other order but I also probably would be wrong.
>>2991824
>Also OP you know this amp sucks by modern standards
Correct. But that's not the whole picture with vintage audio. I am a class D, modern standards person on paper and run vintage McIntosh for my daily listening. I don't try to explain why.
>It looks great, I'd just gut it and put a TPA3552 inside. Unless you want the nostalgia value.
Don't do that unless you get a real burned-out irrepairable husk. You want something modern, just buy something modern.