The Supro Tremolo Pedal (SP1310 £229 UK rrp) is a groundbreaking analog stompbox designed to recreate two of the most desirable vacuum-tube-based modulation effects found in US amplifiers of the 1960s. The Amplitude/Harmonic switch allows the musician to choose between these distinctly different, vintage effects. Amplitude mode provides the traditional, swampy, tremolo sounds generated by bias-modulating the power tubes in the original Supro amps. Meanwhile, the Harmonic mode provides the psychedelic tones of those classic brownface and blonde amps from the early 60s. Supro implemented the unique harmonic tremolo effect within this pedals transformer-equipped output stage to create an amp-like modulation experience.
The Supro Tremolo pedal features preamp and power amp sections, with an actual output transformer deployed to recreate the magnetic saturation and coloration of the original vacuum-tube-based effects found in these historic amps. Along with the standard modulation controls for speed and depth, the Supro Tremolo also features a gain circuit that allows the musician to overdrive the output stage, right where the modulation effects are created. The Gain control sets the amount of “preamp” gain in the pedal. As you turn the gain up, the “power amp” circuit will gradually be pushed into overdrive.
What’s more, an industry-standard TRS expression pedal can be used to control the speed of the Supro Tremolo, with the on-board Speed knob used to set the maximum value. The rate of modulation is indicated by the pulsing LED status indicator.
All Supro pedals are assembled in Port Jefferson, NY, USA, featuring custom-tooled, anodized, brushed-aluminium enclosures, 9V battery or AC-powered operation, rear-mounted metal jacks, easy-access side-mounted battery drawer and studio-friendly, noiseless (click-free), true-bypass switching.