The Guyatone Ultrem Optical Tremolo is an analog tremolo pedal built around optical circuitry that Guyatone describes as based on the classic amp tremolo circuits of yesteryear. It goes beyond a basic tremolo: six Effect Modes cover oscillator-controlled tremolo and manually-controlled volume effects, including an overdrive-style use when the oscillator is disengaged, and each mode has a Sub-Mode reachable with a quick press of the Control Footswitch1.
What it does
With optical circuitry based on the classic amp tremolo circuits of yesteryear, the Ultrem offers several types of tremolo and volume effects, including oscillator-controlled Tremolo and manually-controlled volume effects, with overdrive available when the oscillator is disengaged1. The last two Modes also feature Bonus Modes that allow manual selection of the oscillator waveform via an external expression pedal1.
The oscillator's rate can be displayed in BPM or milliseconds, allowing precise syncing to song tempo or external devices1.
Controls, modes and connections
The front panel gives access to all six Effect Modes, and the Depth and Saturation controls allow precise control of the degree and tonality of the effect1.
| Control | What it does |
|---|---|
| Speed | Sets the rate of the tremolo, front-mounted1 |
| Depth | Precise control of the degree of the effect1 |
| Saturation | Precise control of the tonality of the effect1 |
| Control Footswitch | A quick press accesses the Sub-Mode of each Effect Mode1 |
Rate can be set three ways: tap tempo, the front-mounted Speed control, or an optional expression pedal1.
The dual outputs allow panning of the tremolo effect between two amps, or use as an amp selector/blender in manual Volume Mode1.
Waveforms
In the oscillator-controlled Effect Modes, the Ultrem's CPU offers six selectable waveforms, a variety of Triangle, Sawtooth, and Square Waves. according to RockBoard's PedalPedia, this allows the Ultrem to mimic any tremolo type from the smooth, rolling tone of vintage amps to the tight "helicopter" chop1.
Power
The Ultrem runs on 9V DC, center negative, and draws 80mA1.
With an 80mA current draw1, the Ultrem needs a power supply output rated to deliver that current; a low-current daisy-chain output may not be sufficient.
Where it sits in Guyatone's range
The Ultrem is one of several tremolos Guyatone has made, alongside the Guyatone VT-X Flip Tremolo and the Guyatone VTm5 Veri Trem. For how optical tremolo works and how it compares with other approaches, see Tremolo Pedals.
Videos
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Questions
Does the Guyatone Ultrem have tap tempo?
Yes. The rate of the tremolo can be controlled via tap tempo, the unit's front-mounted Speed control, or an optional expression pedal. The oscillator's rate can be displayed in BPM or milliseconds, which allows precise syncing to song tempo or external devices.
Can the Ultrem run in stereo with two amps?
Yes. The Ultrem has dual outputs that allow panning of the tremolo effect between two amps. They can also be used as an amp selector or blender in manual Volume Mode.
What power supply does the Guyatone Ultrem need?
The Ultrem runs on 9V DC, center negative, and draws 80mA of current. Because of the current draw, a supply rated for at least 80mA on that output is needed.
What waveforms does the Ultrem tremolo offer?
In the oscillator-controlled Effect Modes, the Ultrem's CPU offers six selectable waveforms, a variety of Triangle, Sawtooth, and Square Waves. According to Guyatone, this allows the Ultrem to mimic any tremolo type from the smooth, rolling tone of vintage amps to the tight "helicopter" chop.
Sources (1)
- Ultrem Optical Tremolo by Guyatone, RockBoard PedalPedia, 2026
