Just about every tremolo pedal on the market aims to reproduce classic Fender-amp-style tremolo, but this new version of Effectrode’s Delta-Trem actually uses the correct vintage technology: photocell circuitry coupled to a valve signal path with a pair of glowing 12AU7 valves (although you can swap them out for, say, 12AX7s for different tonal characteristics).
Its basic design ethic is to retain the benefits of an all-valve signal path while engineering out certain shortcomings of vintage amp tremolo units, notably the ‘ticking’ noise that can occur. It also goes beyond the limits of amp tremolo by offering optional stereo operation via twin LFOs, a massive range of waveforms for different trem flavours, tap tempo, and options to add accents for distinct tremolo patterns.
Depth and Speed knobs are as you’d expect with Speed optionally being controlled by a Tap Tempo footswitch. The Shape knob works as a tap divide/ multiply control with eight different timing options in tap tempo mode, but its main role is to morph through the 48 waveforms for the LFO, stored in three banks (Filament, Fluid and Neon) of 16 selected via a rear panel toggle switch.
Whether it’s sine, triangle, square, falling or rising saw or lopsided in-between hybrids, all of the wave shapes here are smooth and musical and between them offer a nuanced variety of tremolos to suit all needs, be that a deep throbby pulse or just a whisper of shimmer. There’s a natural sparkle and warmth to the sound as might be expected with valve circuitry - certain settings contribute more compression and drive than others but always blend extremely well with amp tones, both clean and dirty, and are naturally integrated rather than an effect imposed on top.
Some knob juxtapositions can affect output volume, so that the balance between bypassed and effected sound may not always be exactly as you’d prefer. There’s no front-panel volume knob to instantly even it up, either - however, there are internal trimpots. If you want to get away from standard tremolo, then the Rhythm knob scrolls through eight accented rhythm patterns that can spice things up with a more sequenced effect.
Effectrode’s Delta-Trem is quite possibly the most natural amp-style tremolo you’ll hear in a pedal - with extras.