Its happening again....POPPING sounds from the Mark IV!

[ThatDamnSG]

:x This amps been in two different shops over the past month. Had it back for a few days and today after working fine after I got it back its started making those **** popping and crackling sounds AGAIN!!!! Its had a cap job, a bad pot changed, brand new tubes.....don't know where to go from here. I've sunk $300 into the amp over the past month in tubes and repairs. It does it about a minute or two after being switched out of standby then slowly goes away after about 15 mins. Even with the silent recording pulled it can still be heard coming from the speaker ???? To say I'm irritated is an understatement. I love this amp but its becoming more expensive to maintain than my car!

 

[stomper]

Make sure your tech knows about this page. The good part is when you finally nail it down, your amp should be good for a long time.

http://www.geofex.com/ampdbug/ampdebug.htm

 

[Restless Rocks]

Okay the amp doing the popping when the silent record switch is pulled tells us one very important thing. The problem is isolated to the power supply or the power amp section. There are several different things that could cause it. I have seen several Standby Switches go bad and cause an internal arcing which would pop like heck thru your speaker. Could be as simple as a resistor or as bad as a transformer. I'd swap out the standby switch just to rule it out.

 

[ThatDamnSG]

Okay the amp doing the popping when the silent record switch is pulled tells us one very important thing. The problem is isolated to the power supply or the power amp section. There are several different things that could cause it. I have seen several Standby Switches go bad and cause an internal arcing which would pop like heck thru your speaker. Could be as simple as a resistor or as bad as a transformer. I'd swap out the standby switch just to rule it out.

Thanks for info everyone. I'll have him look that over when I get it back in the shop. My caps were in fact going bad...and the amp sounds a lot better, but now the popping and crackling is amplified even more....probably more power getting to whatever the deal is. Its loud pops usually along with burst of crackling static that sound almost like loud ripping noises. Whatever it is it doesn't effect the actual tone of the amp, just annoys and worries.