I've thought about it but heard it only makes the amp quieter so your volume knob shows less break up but in reality the output is just lower. Did you still maintain the amp's overall volume afterwards?mrperson wrote:You should be fine, you can always muck around with valve types. I've used 12AT7s and 12AU7s to clean up amps before - it does work.
I'd also recommend a more efficient higher rated wattage speaker and under-biasing your power tubes a touch.