I forget to show former and later plate +B voltages with a multimeter. The increased plate voltage brings better audio clarity and headroom. I notice a very clear audio with richness and high frequencies content not only low end, very linear, also the output level pot acts similar as a tube drive control and the input gain pot adjust the discrete low noise transistors mic preamplifier. Compared with a Xenyx X2222USB mixer the MIC2200 is ultra quiet with unnoticeable hiss noises, a top preamp unit, very important for recordings.

