If that sounds familiar, you must be a Whovian (a “Doctor Who” fan, that is), and are therefore familiar – whether you know it or not – with the effect known as the ring modulator. It’s the electronic trickery that gives the evil Daleks their distinct voice. It’s also featured on Black Sabbath’s “Paranoid” guitar solo, ZZ Top’s “Cheap Sunglasses” and South Park’s end credits. Jon Lord’s keyboard sound for Deep Purple also gets some of its more sinister tones from a ring mod.
As guitar effects go, this one’s a little fringe-y. First used to enable stereo broadcast of FM signal from radio waves, it eventually wended its way into early electronic music and sci-fi movie effects. A ring modulator essentially uses two signals, usually one from the instrument and another from an internal oscillator; it then puts out a separate, third signal made from the sum and differences of the two inputs. As pedal guru Dave Hunter puts it, “The result is a little like an octave divider trying to handle two notes at a time rather than the single, pure note that it’s able to deal with, and it coughs up a dissonant mess as a result.”
“…use it sparingly. A little ring modulation goes a long way…”
This process alone would produce a note that sounds nothing like the original note from the instrument. Most effects for guitar are set up so that the outputs keeps part of the main input intact, however. That way, you still retain some of the original signal’s musical intent and dynamics – but in seriously wacked-out form.
Special mention should be given to Harald Bode, who didn’t have much to do with guitar, but a lot to do with early electronic music. In the 1950s, he was one of the first to realize the potential use of ring modulation for music, and teamed up with composer Vladimir Ussachevsky at the Computer Music Center (CMC) at Columbia University, a collaboration that led to numerous innovations in music technology.
A famous early use of ring modulations is Karlheinz Stockhausen’s 1955 composition “Gesang der Jünglinge,” which tells the story of the Book of Daniel when King Nebuchadnezzar throws Shadrach, Meshach and Abednego to the lions (spoiler alert: they’re saved). So while avant-garde composers and sci-fi soundtrack scorers were long hip to ring modulation, it took longer for the rock world to catch up. The ring modulation that Tony Iommi used on “Paranoid” came via studio equipment, not an effects pedal, which weren’t commercially available until Maestro put out the RM-1 in 1971.
Electro-Harmonix released another early classic take on the effect with 1977’s EH-5000 Frequency Analyzer (so essential to the sound of Devo’s Mark Mothersbaugh that he duct-taped the pedal to his guitar), and also went on to produce the Ring Thing. Other well-regarded ring mods include the Pigtronix Ringmaster, Moog MF-102 Moogerfooger, and Randy’s Revenge Ring Modulator from Fairfield Circuitry. Regardless of the maker, you’ll know it when you hear its distinctive tones. Ring modulation is ultimately so distinctive and extreme, for guitarists, the general rule of thumb is: use it sparingly. A little ring modulation goes a long way…