I had this amp working just fine for a while at 94mV on two channels. The bad news is that it caused some noise from the amp on start up. It sounded a little bit like whisker noise. It did go away after warmed up though. The good news is that after the amp warmed up (took some time) it sounded really good. The higher bias did seem to improve sound stage and imaging. It was not a night and day difference however so I am setting the amp back to stock. It's just not worth risking the amp.
BTW durring the summer the amp would get quite hot but not to hot to touch. If you want to play with this yourself I suggest your make sure your amp is well ventilated or has a fan blowing on the heatsink.
BTW durring the summer the amp would get quite hot but not to hot to touch. If you want to play with this yourself I suggest your make sure your amp is well ventilated or has a fan blowing on the heatsink.
What is a whisker noise ? Is it high pitched ? It might be the coils if it is. We use apply some silicone gel to the windings to stop it.
What makes you so sure the higher bias causesd this noise ?
At 94mV it's quite incredible the amp did not become too hot to touch. On the other hand, 10.0 bias is approx. that high. What was the idle current draw at that setting. Were the remaining two channels set at 25mV ? Measured at 12.0V by the way ?
What makes you so sure the higher bias causesd this noise ?
At 94mV it's quite incredible the amp did not become too hot to touch. On the other hand, 10.0 bias is approx. that high. What was the idle current draw at that setting. Were the remaining two channels set at 25mV ? Measured at 12.0V by the way ?
Whisker noise sounds like rustling coming from the speaker. It only happened on start up and was not a big deal. I think the bias did this because the amp did not have any noise before I played with the bias.
I never measured the total current draw. The remaining channels were at 25mV, measured at 12V.
The amp did get warmer, just not class A warm. The only time I was worried about the heat was on a hot summer day. Remember though I was only using the amp on a pair of compression drivers, not regular speakers. I am not sure how the amp would perform if pushed hard on inefficient speakers.
I never measured the total current draw. The remaining channels were at 25mV, measured at 12V.
The amp did get warmer, just not class A warm. The only time I was worried about the heat was on a hot summer day. Remember though I was only using the amp on a pair of compression drivers, not regular speakers. I am not sure how the amp would perform if pushed hard on inefficient speakers.
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