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Demeter Tremulator Plus Review

A classic wobble box, revised and expanded.

Here’s a scary campfire story you can use next time you’re out in nature with young guitarists. First, shine the flashlight upward into your face for demonic effect. Next, intone these words:

“Long ago, in a dark, distant century, there was a soulless time when most players and manufacturers forgot that tremolo was bitchin’.” [Pause for horrified gasps.] “Tremolo was a rare feature, even on cool little combo amps. And that wasn’t the only thing.” [Make ’em wait for it.] “It was nearly impossible to buy a good, vibey tremolo pedal!”

You can stretch it out from there, but don’t end on an entirely dismal note, or no one will sleep. Add this: “However, there were a few lights in the darkness. A few plucky companies built tools to make tones tremble the way Leo and God intended. Manufacturers like James Demeter, with his brave little Tremulator!” [Your audience will visibly relax at this point. Time for s’mores!]

Carrying the Trem Torch
It’s been nearly 35 years since the original TRM-1 Tremulator debuted. Back then, when a flanger was a must-have and tremolo was deemed old-hat, the TRM-1 was the perfect remedy for trem-less amps. The pedal became a mainstay for players including Ry Cooder, Richard Thompson, Jonny Greenwood, Michael Landau, and Ben Harper.

Demeter recently updated his design with the Tremulator Plus. The good news is that it duplicates the sound and features of the beloved original. The other good news is that the added features are cool, usable, and highly musical. (Bad news? Why does there always have to be bad news?)

None of the new controls radically reinvent the effect, but each one adds something nice.

A Classic Reconsidered
Let's revisit the original features before surveying the new stuff. This is an optical tremolo circuit in the blackface Fender vein. There are simple rate and depth knobs, but both have far greater range than on a 1960s Fender amp. High rate settings yield super-fast fluttering—almost approaching ring modulation. At the other extreme, you can order a pizza between pulsations. The depth control can also get extreme, yielding a hard, percussive chop.

I’ve always been of two minds about these wide-ranging rate controls. On one hand, the expanded ranges unlock sounds you can’t get from an old Fender amp. On the other hand, I sometimes find it tricky to dial in the perfect rate/depth balance, despite the simple controls. This isn’t a tap-tempo design, so overly deep modulation can easily mess with your groove. Meanwhile, the rate control’s extreme range means you sometimes have to fiddle around in small segments of the control’s range. Yes, you can absolutely get vintage sounds—and more—but it can require finesse.

New Ways to Wiggle
None of the new controls radically reinvent the effect, but each one adds something nice. There’s now a dedicated gain control, which is more useful than you might initially think. Tremolo is subtractive. It lowers the volume of the quiet part of the waveform, as opposed to boosting the loud part. That means there’s an inevitable energy drop when you engage the effect, and most cool trem pedals compensate with a few dB of extra gain. But there are times when it’s great to be able to fine-tune the level. For example, if you tend to use tremolo on clean-toned passages, but not the loud distorted stuff, an extra shot of gain can make the effect gush more—especially when playing delicately. This gain knob’s modest range can be surprisingly useful.


Excellent sound. Wide rate and depth ranges. New gain, waveform, and bias controls.

No tap tempo. No real-time control.


Ease of Use:




Demeter Tremulator Plus

There’s also a control to fade between traditional triangle-wave modulation and more aggressive square-wave modulation. The square-wave setting lets you nail the sharp-edged pulsation of the quirky Kay Tremolo, a cheapo vintage model that’s acquired a cult following. There are many attractive in-between settings.

The other new addition is a bias control, also with a narrow but useful range. It can add a slight touch of saturation and, like the gain, it has the effect of making the tremolo gush with a little extra presence. High settings sounded great with the vintage-output pickups in my test guitars (a Gretsch Spectra Sonic Baritone and a 1963 Strat).

Inside the standard BB-sized enclosure, the work was clearly done by hand. The soldering is solid, though some of the wire runs seem needlessly long. The metal jacks are chassis-mounted. The components are standard-issue stuff, with op amps handling the gain control and an enclosed opto-isolator providing the throb. The pedal runs on external 9V power (not included) or internal battery connection. A blinking LED indicates the current modulation rate.

The Verdict
The Tremulator Plus duplicates the fine sound of the original, with some nice new shading and colors. But while this pedal hasn’t changed all that much from its initial incarnation, the world around it has. In the ’80 and ’90s, the TRM-1 was a godsend for trem-starved guitarists. But today, there are far more tremolo options, including models with such features as volume-triggered modulation, real-time control, tap-tempo, dual oscillators, stereo output, asymmetric modulation, and greater waveform control. And those are only the analog contenders. Tremolo is one of the easiest effects to model, and numerous digital tremolos offer deeper control and dead-accurate imitations of many tremolo types, from Vox to Marshall to brownface and beyond. But for players whose chief interest is traditional Fender-style trem (with expanded range and color), these pulsations are likely to please. And while $299 ain’t cheap, the price isn’t out of line for a quality, handmade stompbox.

Watch the Review Demo: