DESCRIPTION:
I've never owned a volume pedal but what immediately impressed me about the MVP was that it has a 20db gain boost control and a min control that lets you set up to 50% of level for the heel down position meaning you can set a clean & dirty tone without altering your guitar volume and either quickly switch between them or use the pedal to gradually increase and decrease the gain. On a clean tone you can obviously use it as 2 separate volume levels.

The Tuner output can be used at any volume, with any tuner, without any effect on audio signal. No high frequency loss at any volume. Works with active and passive audio signals. Can be placed anywhere in the signal chain. Improved sweep for ideal volume control, 9v batttery or AC adapter powered.

http://www.ernieball.com/products/pedals/5338/mvp-most-valuable-pedal