Hi - I have a valve mono-block power amp with volume control. The volume control works great when running direct from a single source e.g. cd player. But if I run multiple components through a pre-amp what do I do with the amp's volume control? Do I set it at max and "attenuate" at the preamp? Or does that mean the valves are then running flat out all the time. Does the amp volume control "attenuate" the gain or does it increase the power output? Basically what's the recommended way of setting volume on a valve power amp when using a preamp for volume. Thoughts??

Hi Paulsaints, the volume control only controls the amount of signal sent to the amplifier circuit. Generally, when you connect a preamp to a poweramp with volume control, the poweramp volume control can be turned to maximum, and the total volume then controlled by the preamp.
If the gain is too high or you hear hiss through the speakers with the preamp connected, you can turn down the poweramp volume to a more appropriate level.
Adjusting any volume control doesn’t change the power output capability of the amp, only how much it amplifies the signal by. Most poweramps have a gain of around 25 times at maximum volume control position. With the volume control in the 12 o’clock position it would amplify by about 3 times (if it is a logarithmic pot, as most volume controls are).

AMR-iFi R&D