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TUBE GAIN:
The tube gain control varies the high voltage supply to the preamp tubes.
This allows a variety of tonal response characteristics from the power amp and replaces the limiter
found on typical solid state power amps.
At “10” the voltage is at maximum, providing a dynamic, highly responsive tone.
At “0” the voltage is at minimum, offering a thickened, more compressed tone.
This tone may also be distorted, depending on volume level.
In between settings are best for preventing harsh distortion when driving the power amp to its limits.
The effect of this control increases from moderate to dramatic as the power amp is driven harder.