Some of the Dumble schematics I've seen include a trimmer between the PI plate resistors. According to info on Aiken's site, "When only one signal input is used (ignoring feedback inputs) R1 is usually made 10% - 20% lower than R2 to compensate the unbalanced gains of the two tube sections and make the two output amplitudes equal." So...my question is, does this make an audible difference in the tone? If so, how would I go about adjusting the trimmer if I don't have a scope to measure amplitude? (Plate voltage? Best tone? Sustain?) Thanks in advance for any advice.