The Electro-Harmonix RTG (Random Tone Generator) is a palm-sized synthesizer pedal that produces wild, randomly changing tones over a four-plus octave range1. Unlike most octave and pitch pedals, it does not track or shift your guitar signal: it generates its own tones, and Electro-Harmonix says it creates sensational soundscapes, especially when used with other effects1. The RTG was discontinued in 20191.
What it does: random tones over four octaves
The RTG generates tones on its own rather than processing your instrument. Electro-Harmonix describes it as producing "wild, randomly changing tones over a four-plus octave range" and says it "creates sensational soundscapes, especially when used with other effects"1. Delicious Audio described it as a box that cycles tones, with a stomp to turn the cycle of tones on or off3.
I/O is minimal: just a 1/4″ output jack, so the pedal goes into an amp or the front of your pedalboard and generates its tones there1. An indicator LED alerts you to its on or off status1.
The controls
The RTG keeps its control set small, matching the original 1980 device.
| Control | What it does |
|---|---|
| Rate knob | Controls the speed at which the tones are generated1 |
| Glide switch | Adds portamento, a glide between pitches1 |
| Footswitch | Turns the RTG on or off1 |
| Indicator LED | Shows the pedal's status1 |
That is the whole interface. There is no pitch selection, no waveform choice and no expression input: the randomness is the point, and the Rate knob sets how quickly the tones change1.
History: a recreation of a rare 1980 EHX synth
The RTG is a faithful reissue of a rare EHX synthesizer first introduced in 19801. Premier Guitar reported the reissue in January 2013, describing the pedal as "a faithful reissue of a rare EHX synthesizer first introduced in 1980"2. Delicious Audio likewise called it a recreation of the device box of the same name produced in 19803.
The reissue ran until 2019, when Electro-Harmonix discontinued it1. Players who want the original 1980 device or the 2013 reissue today are looking at the secondhand market in both cases.
Videos
EHX
Joel Gilardini
Prymaxe
Questions
Does the EHX RTG run on a battery?
Yes. Electro-Harmonix says the RTG is powered by a standard 9Volt power supply or a 9Volt battery, and a battery was included with the pedal. No external power supply was required to use it.
Is the Electro-Harmonix RTG discontinued?
Yes. The RTG was discontinued in 2019, according to the Electro-Harmonix product page. It was a reissue of a rare EHX synthesizer first introduced in 1980, so finding one today means looking at the secondhand market.
What does RTG stand for on the Electro-Harmonix pedal?
RTG stands for Random Tone Generator. The name describes exactly what the pedal does: it generates tones at random across a range of more than four octaves, rather than tracking or processing your guitar signal.
Sources (3)
- RTG | DISCONTINUED 2019 | Random Tone Generator - Electro-Harmonix, Electro-Harmonix, 2019
- EHX Launches 45000 Looper & Random Tone Generator, Premier Guitar, 2013-01-23
- Guitar Pedal News: Electro-Harmonix RTG And 8 Step Program, Delicious Audio, 2013-03-05
