I would like also to add to the "opamp equation" question, the factor of trimmer. The pcb of opamps is currently using a single turn 10% Bourns 3362 trimmer per opamp. (two) What about the replacement with the following trimmer.
Y4053200R000J0L Vishay Precision Group Foil Resistors | Mouser Greece
Y4053200R000J0L Vishay Precision Group Foil Resistors | Mouser Greece
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You got bad case of upgrade-itis
Curious- Why are there thick ceramic spacers between the power devices and their heat sink on one side and not the other ?
Hehe nice one
The right side of the amp is the side which I have recapped. ELNA Silmics are surely bigger. I have also used an aluminum oxide ceramic insulator from AAVID. Better thermal performance, you never need to replace it mpla mplah for the precious Sanken SAP15. They are very expensive and hard to find. (at least the originals)Also this upgrade gave me the opportunity, (since it's 2mm thicker) to put the whole channel pcb on rubber washers for reduced microphonics. Something that the discreet line amp pcb had already from "mama" MF.
And to finally answer your question: I haven't start the left channel yet.
4180G Aavid | Mouser Greece
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One thing to watch out for when replacing these opamps is oscillation. More modern opamps are generally faster and wider band, which is a good thing IF the circuit is designed for it.
Many people have replaced opamps with newer/faster ones and ended up with singing amps.
Doesn't always happen but you need to be aware and have some way of checking for it.
Jan
Many people have replaced opamps with newer/faster ones and ended up with singing amps.
Doesn't always happen but you need to be aware and have some way of checking for it.
Jan
I feel that MF has designed the pcb with the opamps exhaustively for this kind of cases that could cause such problems with opamps.
I surely don't know what will happen with a much newer op amp. But I know that other amplifiers, who people tried to upgrade opamps, didn't even have a trimmer for op amp offset voltage fine tuning.
So I am just curious to see the end result.
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