The most underutilized sonic tool that electric guitarists have is built right into their instruments: the volume and tone dials. Most players tend to leave their guitar’s volume up full and set the tone knobs in one place and work from there, but with a little practice it’s easy to get used to using these potentiometers or pots — which are contacts that control voltage — to sculpt interesting sounds.
The basic function of the volume knob is to change the level of your guitar’s volume output in a smooth and even way. But there’s more to it than that. Some players use the volume knob as a means of boosting their signal to make solos pop out. For example, if you keep your volume dialed in at seven or eight and perhaps lean on your amp a little more for output, you’ve got two or three more notches to ride your loudness up via the knob when it’s really time to burn. No need to spend money on a volume pedal, and unlike distortion or overdrive pedals this doesn’t change your sound much.
That said, however, the volume knob can help you conjure a variety of tonal characteristics that can come in handy provided you play with dynamics. Using a volume knob in this context can allow such cool maneuvers as having different tones for verses and choruses, or for various styles of music. To get a handle on how your guitar’s volume dial or dials can affect tone, plug in and fire up your amp until it’s growling with overdrive. Start with your guitar’s volume pot at 10 and begin rolling the dial back in increments. As you go, you’ll hear not only a decrease in loudness, but your sound will clean up and experience variations in its harmonic characteristics.
Jeff Beck is a master of using his guitar’s volume knobs in this manner as well as for swells, that sweeping violin-like sound at the beginning of his Blow By Blow classic ’Cause We’ve Ended As Lovers,” an instrumental dedicated to another master of the volume and tone controls, the late Roy Buchanan.
Now, let’s consider the tone knobs. Eric Clapton was one of the first guitarists to realize the power within those unassuming plastic spinners. His famed “woman tone” sound during Cream relied on rolling the pots on his Gibson Les Paul Standard, SG or ES-335 all the way off and turning the treble and midrange of his superbly overdriven Marshall amps high. Similarly, jazz guitar players who are looking for a classic tone roll their pots back until they get in the Wes-Benson-Burrell-Pass-etc. zone.
If you play with your guitar’s tone controls all the way up, your tone is going to be trebly and bright — possibly even painfully shrill at high volumes. To get a handle on their range, get a clean sound cooking out of your amp and play at every numeral stop on your instrument’s tone pot dial. And for multi-pickup models, do that for each individual pickup and all the blended settings. Find a few positions you like, and while playing a tune you know by heart, roll to different settings for verses, choruses and solos and see how tonally diverse and interesting things become. On stage this can be a very impressive way to create fresh sounds — subtle, but noticeable — without relying on pedals or amp channel switching.
But add some effects to the blend and the results can be even more interesting. Keyboard-like tones can be generated by rolling off the tone pots and employing digital delay, expanding the sound of your band without overstuffing the van, and the gentle application of a phase shifter or wah-wah can bring an interesting voice to warm, low tones. Jimi Hendrix’s “Pali Gap” is a classic example of the latter.