The JHS Harmonic Trem is a tremolo pedal from JHS Pedals' budget 3 Series line, one of two new 3 Series pedals the company debuted alongside the Octave Reverb1. JHS describes the 3 Series as "a collection of pedals designed to give you affordability and simplicity without compromising quality," and each pedal is made by the company in Kansas City, MO1.
What it does
The pedal carries two tremolo voices on a toggle. JHS puts it plainly: "Toggle up is a great sounding amp trem, while toggle down is our take on harmonic trem effect"1. Toggle up gives a standard amp tremolo, the effect familiar from vintage amps. Toggle down engages harmonic tremolo, and JHS describes it as "a really fun way to get a different unique tremolo sound that sometimes crosses over into a Univibe-type effect"3. Delicious Audio describes the result as "a dreamy effect similar to the Uni-Vibe," on a pedal with three knobs and a two-way toggle2.
JHS itself frames the harmonic mode as something a little stranger than a plain tremolo: "It's a really fun way to get a different unique tremolo sound that sometimes crosses over into a Univibe-type effect"3. Pedal of the Day's reviewer heard the same character, calling the harmonic mode "a dreamy effect similar to the Uni-Vibe"2.
Controls
| Control | What it does |
|---|---|
| Three knobs | Speed, shape and level of the tremolo effect1 |
| Toggle, up | Amp tremolo mode12 |
| Toggle, down | JHS's harmonic tremolo mode12 |
JHS says the three controls and toggle "offer a wide range of sounds, perfect for beginners and profess[ionals]"1.
What reviewers said
Pedal of the Day reviewed the pedal in May 2025 and placed it in the context of the wider line: "The 3 Series from JHS Pedals is a fantastic and affordable way to get into this crazy effects world we all live in"2. The same reviewer praised the look of the pedal, calling it "this clean white beauty" that "looks and sounds amazing"2.
"The 3 Series from JHS Pedals is a fantastic and affordable way to get into this crazy effects world we all live in"
Where it sits in JHS's tremolo range
The Harmonic Trem is the simple, low-cost entry in JHS's tremolo lineup, sitting alongside pedals like the Honey Comb Deluxe and the tap tempo Kodiak. For more on the effect type itself, see the site's page on Tremolo Pedals12.
Videos
Ryan Lutton
Musicmaker
Brad Dollar
Sources (3)
- 3 SERIES HARMONIC TREM, JHS Pedals
- JHS Pedals 3 Series Harmonic Trem, Pedal of the Day (www.pedal-of-the-day.com), 2025-05-25
- THE JHS OCTAVE REVERB AND HARMONIC TREMOLO, JHS Pedals
