The Rounder Sounds Zebra-Trem is an amplitude tremolo, the effect type that rhythmically raises and lowers your volume, with a twist: you can edit the LFO waveform on the pedal itself. Delicious Audio's product page describes it as allegedly "the only tremolo pedal with on-pedal waveform editing," and it ships with 16 factory waveforms to start from12. For a player used to choosing between sine, square and triangle on a standard tremolo pedal, that means shapes like "Shrug" or "Groove 16" are on the menu, and your own drawings can be saved.
Waveforms you draw yourself
The pedal carries 16 factory waveforms, listed by Guitar Pedal X as Sinewave Triplets, Sinewave 16ths, Square Wave Triplets, Square Wave 16ths, Sawtooth / Ramp Up, Reverse Saw / Ramp Down, Triangle Wave Triplets, Triangle Wave 16ths, Alternate Triangle Triplets, 2 Molars, 1-345678, Sine1234, Shrug, How Soon Now (Smiths!), Sine1aa3a4a and Groove 162. Any of these can be edited on the pedal, and the result can be stored in presets1.
One practical limit: the display shows 11 characters, so waveform names appear somewhat truncated2.
"A really sophisticated and super versatile, great sounding Tremolo effect."
Guitar Pedal X's reviewer described the pedal's output as having "a warm richness of tone to their output, and a somewhat bright profile"2, and in a December 2024 roundup called it "still the most sophisticated waveform generator in many ways overall"3.
Controls, tap tempo and connections
The knobs are simple: Level sets the overall level, alongside Depth and BPM controls1. The Tap Tempo footswitch can replace the BPM knob in setting the tempo of the LFO, and taps divide patterns into beats, which is how the rhythmic waveforms line up with a song21.
| Control | What it does |
|---|---|
| Level | Sets the overall level1 |
| Depth | Depth control1 |
| BPM | Sets the tempo of the LFO1 |
| Tap Tempo footswitch | Can replace the BPM knob; taps divide patterns into beats21 |
The jack and port layout, per Guitar Pedal X2:
- In and Out jacks
- External Tap Tempo jack
- Micro-B USB, for firmware updates and to transfer app waveforms
The USB port is for firmware updates and transferring waveforms from the app, not for powering the pedal on a board2.
Price
Guitar Pedal X's December 2024 roundup lists the Zebra-Trem at $2293. The November 2024 review gave the price as $229 / €212 / £169 plus £20 delivery and equivalent2; the euro and pound figures come from that review and the sources differ on how the non-US pricing is stated.
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Questions
Can you save custom waveforms on the Zebra-Trem?
Yes. Delicious Audio's product page notes the pedal's ability to store your created waveform in presets, so a shape you have drawn on the pedal can be recalled later rather than redrawn each time you use it.
What does the USB port on the Zebra-Trem do?
The Micro-B USB port is used for firmware updates and to transfer waveforms created in the companion app onto the pedal, according to Guitar Pedal X's review. It is not a power connection in the usual sense of pedal power supplies.
Who designed the Rounder Sounds Zebra-Trem?
Guitar Pedal X's review names Bill Neal as the designer and notes that the Zebra-Trem is his first ever official pedal, released under the Rounder Sounds name.
How much does the Rounder Sounds Zebra-Trem cost?
Guitar Pedal X listed the Zebra-Trem at $229 USD in its December 2024 roundup. The earlier November review gave the price as $229 / €212 / £169 plus £20 delivery and equivalent.
What did Guitar Pedal X say about the Zebra-Trem?
Reviewer Stefan Karlsson called it a really sophisticated and super versatile, great sounding tremolo effect, and in a later roundup described it as still the most sophisticated waveform generator in many ways overall.
Sources (3)
- Rounder Sounds Zebra Trem, Delicious Audio, 2024-06-17
- Guitar Pedal X, Guitar Pedal X, 2024-11-13
- Guitar Pedal X, Guitar Pedal X, 2024-12-19