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VCB/VVR kit for cathode-biased amplifiers

VCB kit for variable power control of cathode-biased amps

VCB is a method for controlling the power supply voltages within a valve amplifier. By controlling this voltage, you can control the amplifier's power output. VCB provides a continuously controllable voltage, and you can rotate a knob to get as much or as little power output as you like. The reason why this is a popular upgrade for valve amplifiers is that you can get the amplifier's natural power valve distortion at much lower room volumes.
      VVR was designed and refined by Dana and Richie Hall of Hall Amplification. The Amp Maker version is called VCB, and this version, VCB1, is for cathode biased amps. It's been successfully fitted to many amplifiers, from Champs, Deluxes, 18Wers, etc. It's also suitable for most Amp Maker kits.

Easy to build

There are several ways to implement VCB in a valve amplifier. This section of the InfoCentre here shows the detail. On the 1-5 complexity scale that I use for amp kits, it would rate a 0.25. Allow perhaps an hour for planning and double-checking your cable runs and another 30 minutes or so for building the kit and wiring it in. In fact, the hardest part is safe handling of the central component - the MOSFET. Unlike the sturdy old-fashioned valves inside your amplifier, the MOSFET is very easily damaged by static electricity.

InfoCentre links:

A handful of components allows you to control the voltages inside your amplifier, and this gives you control of its power output

Price: £18.50
inc VAT