Anyone have the proper idle current/bias settings for this amplifier?
Running about 8mv drop across the 0.1ohm resistor at idle with an 8ohm load connected. Seems kinda hot.
Running about 8mv drop across the 0.1ohm resistor at idle with an 8ohm load connected. Seems kinda hot.
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You don't set bias with a load. A slight (normal) DC offset could affect the readings.
I don't have this diagram but Rockford give 2mv for a lot of amps. For me, that's a bit high, especially on larger amps. I generally use 1mv if I'm measuring but generally just increase (from the full CCW position) the bias until I just see a small increase in current draw from the 12v supply.
To confirm that there is enough bias, connect a load (2 ohm or 4 ohm) and drive the output to about 1v. Run a sweep to 20kHz to check for distortion. At 1mv, there shouldn't be any but you can increase it slightly if there is.
I don't have this diagram but Rockford give 2mv for a lot of amps. For me, that's a bit high, especially on larger amps. I generally use 1mv if I'm measuring but generally just increase (from the full CCW position) the bias until I just see a small increase in current draw from the 12v supply.
To confirm that there is enough bias, connect a load (2 ohm or 4 ohm) and drive the output to about 1v. Run a sweep to 20kHz to check for distortion. At 1mv, there shouldn't be any but you can increase it slightly if there is.