good day bros. I am repairing a Mosconi AS 400 4 channel amp. Need help. The problem is, when ever you turn on the amp an audible popping sound comes out in all the channels. There is no popping sound during playback, only when you turn it ON ,Even with out the RCA 's input connected to the amp. The popping sound is not really loud. The amp is only 4 months old. I measured the Vdc output, it is jumping to 0.6Vdc to 0.8Vdc when pop sounds come then goes back to 0.005Vdc again. I checked all components, but i can not find any fault. Before there was no popping , only after we had used the amp in long period of time at high volume after that the problem begin to come out. What maybe the cause of this sound. can it be eliminated?
Good day. Thank you Perry for the response. Her is the Hi Res photo of on channel.
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This type of amp controls the output (on/off) by controlling the supply voltage for each of the op-amps near the bias pots. The attached diagram should be similar.
Do you have a delayed supply for those op-amps?
Check the regulator components. I've seen them develop bad solder connections in the larger amps.
Do you have a delayed supply for those op-amps?
Check the regulator components. I've seen them develop bad solder connections in the larger amps.
Thank you Perry and Ultra, it will definitely help then let me go over it and update you with my findings.
Just curious if you have solve the popping sound issue? I've the same situation and still finding the root cause....🙁