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OPA1642 or LM4562 in IVY III which did you like better?

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Hi,
Still playing with B3.... ? Go for AK dac.
I have done so with lme49990... not on browndog adaptor...smd melf feedback resistor direct on pins 1uf between -+rails...polystyren caps, wishay resistors... and don*t forget to cure oscilations on DAC regulators that i mentioned or not. I also changed opamps on regulators....done a lot of things Power supply dual a class from DIYzone with opa627 ...not opa134!!! Dig 5V was Salas.
So just output stage is not enough for final result.
At the end it was far above modified Minimax dac.
opa1642 or LM4562 sound very similar to my ears. To bright. No life ...
or try dual ADA4898-2 very good opamp and can be soldered without any adaptor.
 

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Hi.
i have done that...but not dramatically better. Tried also with opa627 and lme49990 with better results. And tried with different bias values...i think at the end the best for my ears was around 10ma or less. The sound has more speed and attack, not to make it softer( that was how i heard). A little dark sounded opa627 becomes more alive.
 

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