[review] Electro-Harmonix Nano RTG Random Tone Generator (by Bieke)

THE RTG or Random Tone Generator is a synthesizer pedal, originally designed by Bob Bednarz and first released in 1980. It is one of the wackiest Electro Harmonix pedals, only few were made and the old EH1300 RTG pedals are super rare, I have never seen one.  The original RTG looked a bit like the EH4600 Small Clone or EH4800 Small Stone, it had the same casing and control layout, but it did not have a footswitch, an input and no status LED either.

Electro-Harmonix released a reissue of this rarity and after I have seen and heard it in action at a live concert by a local band Mon-o-Phone, I was anxious to give it a try myself.

And do a review of course.

Electro-Harmonix Nano RTG - Random Tone GeneratorTHE LOOKS

The reissue RTG comes in the nano size enclosure and let me just say that I absolutely love this enclosure, not too big, not too small, it is a light die cast metal casing, ever so practical to put on a board or to toss in a gigbag and carry around.

The reissue RTG has the same controls as the original, a Rate control to control the speed of the random tone sequence and a Glide mini toggle to switch from pulsed tones to portamento. Then there is the output to connect the RTG to an amp or to other effects.  The output is compatible with instrument or line-level inputs. And the familiar Boss type 9V adapter plug. Also the graphics are reminiscent of the original, black background with RTG printed in red.

In addition, the RTG now also has a footswitch and a red status LED.


As a standalone synth pedal it is relatively limited. It produces a continuous random sequence of bleep and bloop sounds. The randomly-produced tones range over 6 octaves between 20Hz and 1kHz. The Rate knob controls how often the tones are produced. As you turn the Rate knob clockwise, the generated tone changes more often.  The range of the Rate is 5 seconds to 0.1 seconds. The Glide Switch adds portamento or a glide in pitch between the tones, which produces a smooth transition from one tone to the next. There is no real pattern or logic behind the tone sequence, it just starts with a tone and the next one can be higher or lower and the next one as well, and the next one, you get the idea. It is random and unexpected and unpredictable.

The tone of the RTG has an analogue warm feel to it, sounds a bit like a vintage modular synth, but it really is a digital effect. And as such, a real gimmicky pedal, a bit like a sample and hold effect, but if you are a creative sound experimentalist, it can become a useful addition to your arsenal.

As with most effect pedals, the real fun begins when you start being creative and with the RTG, this means using it with other effects or sound sources. Cool loops or patterns can be created by using the RTG in conjunction with distortion, modulation or time based effects. Especially by adding a delay to the RTG's signal chain, you can get rhythmic random tone sequences, that can turn out to be surprisingly musical. This works best when you dial in a slow rate and with dotted eights or ping pong delay and such. With modulation, especially ring modulation, you can get some weird dalek sounds, envelope filters, and pitch shifters, can dynamically and dramatically alter the tones produced by the RTG.

Good fun.


So you have every pedal, got everything covered, you are done with pedals. Ask yourself. Do you have a pedal that bleeps ? If not, the RTG is an addictive little pedal that you can use every once in a while to make some crazy bleeping sounds, just for the fun of it.

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