Hi Shaan, what is the best BIAS configuration to obtain maximum fidelity from this amplifier and the best sound quality?
Hi Cejas.
200mA output stage, 10mA VAS.
Use standard LR network at output for best stability. 10 turns of 1mm enameled wire wound on a 10ohm 2watt resistor will be sufficient.
200mA output stage, 10mA VAS.
Use standard LR network at output for best stability. 10 turns of 1mm enameled wire wound on a 10ohm 2watt resistor will be sufficient.
Whether it is influenced by any differences in build or not, I cannot say. But I ofcourse started out at the standard spec. but was not entirely happy, on my four monoblock builds each supplied by Samy's 600w SMPS's and with Exicon's in the output stage.
I have other Latmos based amps and they are all running higher bias, something that Shaan specifically set out to avoid the necessity off.
Still, raising the bias to 2½-3 times the specified, I cannot remember the actual bias value, but total power consumption is now around 65w/Ch.
Improvements were mainly 3D imaging and spatial resolution and the low end performance, not as lean.
A friend borrowed the 2x2 amp's with std. bias and raised bias and also highlighted the improvements. He didn't want to return them 🤣
I've used them also with my smaller Apogees and it was magic.
But you should just try it out yourself - given that you have sufficient cooling, it's just a matter of dialing it back if you don't like it.
Check the biasing sections in the setup guide. It's all detailed in there. Shared in post #1.
No, but if I remember right the std. bias yielded about 27w consumption at idle.
In reality I biased it as you do a classic Threshold power amp, be it SA/1-SA/3 or S200-S500, stable temperature = ensuring fairly stable thermal conditions also at load. aiming for the 45-50C range.
Use that for a guidance rather than the specific bias current!
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