Peavey Butcher amp

[loudmouth]

Can I remove 2 of the tubes to half the wattage? If so, which ones? Any mod advice?

[Chuck H]

Any four power tube amp can be reduced to half the wattage by removing two of the power tubes. You need to remove either the two inner OR the two outer power tubes. Never pull two tubes from on side, as in the two left tubes or the two right tubes. If you pull two tubes the impedance will need to be adjusted so the two tubes in the amp have the correct load. Set your impedance selector for half the load you are plugging into. As in, if you have a 16ohm cabinet, set the impedance selector on the amp for 8ohms.

Don't expect half power to be half as loud. It's not. It's only 3dB less loud than at full power, so, not much quieter. Reducing speaker efficiency can help more. If your using a 4x12 cabinet you could rewire it to run only two of the speakers. That will reduce efficiency by another 3dB and combined with the 3db cut from pulling two power tubes you'll have a total cut of 6dB. NOW your half as loud. Be sure you know the ohmage of your cabinet when rewired and set the impedance selector on the amp to half that impedance with two power tubes pulled.

As for mods... What do you want the amp to do that it doesn't do now??? A mod should have a goal other than just an arbitrary alteration of the sound. If you have a schem you should post it and let us know how you want to change the sound.