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There are differences between The Truth and a passive attenuator based control

Posted by 1973shovel on March 11, 2011 at 13:47:45:
The input and output impedance, and the resulting issues those impedances create, always kept me away from a passive volume control
Here's information I've lifted from the Horn Shoppe site:
"It has an input impedance too high to measure, output impedance is a couple ohms, bandwidth is to 60Mhz, slew rate is a couple hundred V/microsecond.
There are no capacitors or resistors in the signal path. There is no potentiometer in the signal path.
It uses photo cells to control the volume. It does not use optocouplers.
It is an "active" device and suffers none of the "problems" that "passive volume control/pre amps" have. It can drive long (30 feet) cables with ease."