Hi, I noticed a difference between left and right channels so I decided to open up the PLD1100 and take some measurements. I found that left channel is sitting at 90 mv and the right is sitting at 240 mv. So my question is what is the proper biasing voltage? Any help would be appreciated. Yes I asked Parasound and was told 2 volts, I don’t think that is correct.
According to circuit design, designer usually design the bias VR value that half turn will fit their application, so that this model VR is 1K and you can try set it to 500R to see what the is BIAS result and you can judge which one is correct.
If the voltage is measured by one of the source resistor (10R), according the output MOSFET heatsink size, I think the right channel 240mv (24ma) is correct.
Yes I checked at R140 and R141, I will set the other channel for 240 mv 24ma also, thank you Patrick101!
Ok this is what I’ve found to sound best. It involves leaving the cover screws off for a bit because the cover will come on and off several times to get there. What I’ve found is 180 mv seems to sound best and perform best if anyone else is interested. Thanks again patrick101 for leading me in the right direction.