#1
My peavey bandit is showing about 100mv dc at the speaker terminals. That seems a little high although im not sure.

Can anyone tell me if that is bad or acceptable? And how can i fix it? Please?
#2
From what i can tell ss amps should read about less than 20mv dc at the speaker terminals. 2-300mv dc can damage speakers and ive experienced this on ss radio amps. I think i will do a little bit of experimenting by testing the pre-amp out for dc and then using another peavey's preamp into the power amp out and check the speaker leads for dc. Hopefully there will be a difference and provide a clue as to were the dc offset is coming from.
The last amp that did this i had repaired at a shop and got slammed with a 200 dollar bill and a 25 dollar part. Thats more than the amp is worth and i also dont want to sell the amp as a lemon. Any info would be appreciated.
#3
It will almost certainly be the biasing on the output transistors being unbalanced. Probably because one of them is on the way out.
Gilchrist custom
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Marshall JTM45 clone
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Marshall 18W clone
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Atomic Amplifire
Marshall 1960A
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Cathbard Amplification
My band
#4
Thank you Cathbard! The results of the test are this. Both amps suspect bandit and special put out 40mv dc until the power knob it turned. Then , both show 120mv at the speaker.
With the preamp to power amp in... bandit pre to special pwr showed 47mv no matter what the power knob did. Special pre to bandit pwr showed the 47mv until the power knob inceased the mv to 120mv. So i would suspect the bandit's power amp. But really, both amps regularly put out over 100mv dc so it seems kind of normal.
Last edited by geo-rage at Feb 28, 2017,