Q: I have two identical tube guitar amps, but they really don’t sound the same. When I have them dialed for the exact same settings, one is louder and bassier, the other is quieter and has a more mellow top end. What’s going on here, shouldn’t they be the same?
A: There will always be some variance between “identical” tube amps, depending on tube age and wear, speaker age and wear, amount of use/abuse, and also because of the tolerance variances in the components used by manufacturers.
However, if there is more than a subtle or minor sonic difference, it’s likely that the bias is set differently on the two amps. We suggest taking the amp to a qualified technician who can verify and adjust the bias setting. This should greatly equal out the response of the two amps.