Peavey Invective Crackle and Noise
Posted: Wed Mar 31, 2021 9:07 am
Hi Guys,
i have a problem with background noise on my amplifier.
You can hear strong scratching and sizzling on recordings.
I then took a closer look at the amp and first came across a V1 microphone tube. I then replaced all the preamp tubes. Unfortunately, that didn't fix the problem. Then I checked whether the power amp tubes were set correctly. The grid voltage was set to 23mV (23mA) and the V10 tube only ran at 19.8 mV. That means a tube is not matched. I then increased the grid voltage to 26mV. Background noises are still there.
Then I swapped the two middle tubes with the two outer ones and operated the AMP in Half Power mode so that I can switch off the one that didn't fit. Unfortunately, that did not do any good either.
Then I played around with the gain and noticed that it gets stronger the more I turn up the gain.
The background noises sound like that of an old vinyl record.
Then I watched a couple of videos on Youtube and was able to hear the background noise in the following video. So it doesn't seem to be a problem specifically with my AMP.
https://www.youtube.com/watch?v=WCxhVDWx9EU&t=1309s
Can someone help me with this problem?
Best regards
i have a problem with background noise on my amplifier.
You can hear strong scratching and sizzling on recordings.
I then took a closer look at the amp and first came across a V1 microphone tube. I then replaced all the preamp tubes. Unfortunately, that didn't fix the problem. Then I checked whether the power amp tubes were set correctly. The grid voltage was set to 23mV (23mA) and the V10 tube only ran at 19.8 mV. That means a tube is not matched. I then increased the grid voltage to 26mV. Background noises are still there.
Then I swapped the two middle tubes with the two outer ones and operated the AMP in Half Power mode so that I can switch off the one that didn't fit. Unfortunately, that did not do any good either.
Then I played around with the gain and noticed that it gets stronger the more I turn up the gain.
The background noises sound like that of an old vinyl record.
Then I watched a couple of videos on Youtube and was able to hear the background noise in the following video. So it doesn't seem to be a problem specifically with my AMP.
https://www.youtube.com/watch?v=WCxhVDWx9EU&t=1309s
Can someone help me with this problem?
Best regards