If you simply want to increase and lower your volume with your foot in the same way that youâ€™d adjust the volume knob on your guitar, the only things you need to worry about are how well the pedal is constructed, and whether it colors or attenuates (i.e., "sucks") your tone. If you are hoping to use your volume pedal creatively to get pedal steel or bow-like volume-swell effects, however, its response will be critical. You'll want to know whether the pedal goes to full volume quickly or gradually, and whether you can adjust the response if the stock setting doesn't work for you. You'll also want to determine if the pedal feels good physically—is it the right size for your foot, is the treadle motion comfortable, and does it provide the right amount of physical resistance when moved?
There are also some more objective considerations when it comes to selecting the right volume pedal. For example, is a mono pedal okay, or do you need stereo for some reason? Does your guitar have passive electronics, or do you need a pedal that can handle the hotter output of active electronics? Does the pedal employ a standard potentiometer to regulate the volume, or more exotic technology such as a photocell? Will you be using the pedal in the studio around open microphones where mechanical noise can be an issue? And then there are extras, such as a dedicated tuner output, a "minimum volume" control that allows you to set the heel position to a fixed volume and then push the pedal down for solos, and additional bundled effects such as wah or fuzz.
The six volume pedals presented in this roundup provide a good overview of what’s available. Half are passive, and half require batteries or AC adapters, two are stereo, two have tuner outputs, three have minimum volume knobs, and one has an adjustable response curve. None of the pedals provides any additional effects, and though they range on price from a low of $29 (Behringer FCV100) to a high of $182 (George Dennis GD020, they typically represent the most basic model offered by each manufacturer.
The pedals were first tested using a PRS Custom-24 Brazilian connected to a Rivera Chubster 55 combo, then those results were double-checked with a Fender American Stratocaster connected to a ’70s Fender Twin Reverb, because volume pedals behave differently when used with different gear. To test for noise under pseudo-laboratory conditions, the pedals were further subjected to a “white glove” noise test by being plugged directly into the high-impedance instrument input of a Mackie Onyx 1220 mixer and monitored at high volume through AKG K240 studio headphones. Low-noise Mogami cables were employed in all tests. To maintain an “apples” and “oranges” perspective, the six pedals were tested in two groups: passive and active. (Note: None of the active pedals came with AC adapters, so they were tested using brand new Energizer 9-volt batteries.)