Best modulation pedals

A phaser splits your signal, shifts the phase of one copy through a series of all-pass filter stages, and recombines them. Where the copies cancel you get a notch; sweeping the filters sweeps the notches, and that movement is the effect.

The Phase 90 has one knob. There is no depth control and no mix control, which means you cannot dial a subtle phase — you get the Phase 90 amount or you get nothing. For a lot of players that is the appeal.

Dunlop publishes no current draw or impedance figures. Powering it is straightforward regardless: any 9 V supply.

Chorus takes a delayed copy of your signal, detunes it slightly with an LFO, and mixes it back. The delay time is short — a few tens of milliseconds — which is why you hear thickening rather than a distinct repeat.

The CH-1 gives you E.Level, EQ, Rate and Depth. The EQ control is the differentiator: most chorus pedals give you rate and depth and nothing to shape the result.

It is a bright, clearly digital-voiced chorus. If you want the warmer, murkier analog bucket-brigade sound, that is the Small Clone below.

Analog chorus uses the same bucket-brigade delay line an analog delay does, at a much shorter delay time, with an LFO modulating the clock rate. The high-frequency loss inherent to the delay line is why analog chorus sounds warmer and murkier than digital.

Rate knob, Depth switch, mono output. No mix control, which means it is always doing a fixed amount — easy to use, impossible to make subtle.

EHX publishes no electrical figures for it. It runs from a 9 V battery or any standard supply.

Tremolo modulates volume, not pitch or phase. That makes it the simplest modulation mechanically and the one that changes a part's feel most — a slow deep tremolo under a sustained chord does something no chorus can.

The Flint offers three tremolo circuits with different characters plus three reverbs, at 24-bit/96 kHz, with selectable true or buffered bypass.

The 300 mA minimum is published and it is the constraint. Several common isolated supplies top out at 250 mA per output.

We are not picking this one in a modulation roundup. It is a good delay and its modulated delay modes produce a chorus-like thickening, which is why people reach for it here.

The difference is that a modulated delay modulates the repeats. A chorus modulates a copy of the dry signal at a very short delay time and mixes it back at full level. The first adds movement to an echo; the second thickens the note you are playing right now.

If you want the note itself to shimmer, buy a chorus. If you want your delay repeats to move, the Flashback's modulation is exactly right and you do not need a separate pedal. The delay roundup covers it there.