I feel pretty safe they are correct and good caps, I recaped it myself  using a kit from Martin in 2016! :=)

And it has sounded beutiful eversince.. i actually think som of that adventure is here i the forums somewhere... steep learningcurve.

No... the change in sound came came a few weks ago when i fixed the cracked PCB and changed out all the Darlingtons.

I noticed a crack in the ceramic coating in one of the emitter resistors, so perhaps change them out and also replcae the trimpots for 25 turn ones to get even more exact on the idle current..but i feel this small deviations now are still within the range, so shouldn't effect sound that much..

Found this while googling, does the idle current realy chnage sound this much?

The idle current is important, mainly to avoid crossover distortion.
If set to low, the distortion will cause a shrill and harsh sound and the tweeters will easily be overloaded due to the amount of higher harmonics.
If set to high, the output stage will heat up and the bottom figure on your electric bill will increase unnecesarily.

If you can set the idle current the emitter resistors are fine.
And since the capacitors apparently can be ruled out :-) and I take it your repairs to the board are fine and double-checked, I would suspect the darlingtons.
Can we see a photo or two?

Martin

Here they come, new TIP147 and TIP142 in situ and the old bunch

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If the old ones are still good, I suggest you fit them back.

Martin

...so the old lady is back sounding like before....

Here are the new TIP's upclose.... realy bizzare if they are fake, or just "new".. but i guess I just proved that they absolutely made a difference.

Thanks all for the help, as the saying goes, if it ain't broke don't fix it!

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...so the old lady is back sounding like before....

Here are the new TIP's upclose.... realy bizzare if they are fake, or just "new".. but i guess I just proved that they absolutely made a difference.

Thanks all for the help, as the saying goes, if it ain't broke don't fix it!

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Those darlingtons look nothing like the real thing.
Wrong lettering, no date code, - even the housing is wrong.

Good job!

Martin

Very interesting thread, I would like to see how the fakes measure up on a transistor tester 😏

craig

I have one of these https://youtu.be/9sbfdtYDPCM

Its mostly very accurate, for the right applications...never tried darlingtons before on it..

So it identfies them as regular NPN or PNP tranistors with a hfe of 24-50 (!) quite uneaven between the units...and ofcourse i was expecting more like 1000

and forward voltage between 900-1100mV so atleast that sounds normal?