Electro-harmonix: stereo clone theory, stereo pulsar, and stereo polyphase.(GEAR: Stompbox Fever)(Product/service evaluation)

THE STEREO CLONE THEORY, STEREO PULSAR, and Stereo Polyphase are essentially more compact, stereo versions of already existing mono effects pedals. All three feature true-bypass switching, and are fitted with industry standard 2.5mm barrel-style power-supply jacks, instead of the mini-plugs found on many older EH pedals. The Stereo Clone Theory and Stereo Pulsar accept standard 9-volt/100mA power supplies (such as the optional US96DC-200BI), though you still have to remove four screws on the bottom of the units to replace their single 9-volt batteries. The Stereo Polyphase uses a provided 24-volt/100mA power supply, and it cannot be powered by batteries. The pedals also feature sturdy die-cast housings, rather than the relatively unsubstantial sheet-metal enclosures of their larger forebears.

STEREO CLONE THEORY CHORUS VIBRATO

Poised mid way between the large Clone Theory and the one-knob Small Clone, the Stereo Clone Theory ($159 retail/$118 street) has Depth and Rate controls, along with a switch for selecting Chorus 1, Chorus 2, or Vibrato. The Rate control covers a generous range--from ultra slow to reasonably rapid--and the speed remains the same when you switch between effect types (if you match the tempo of a song while using one effect, it will remain locked in when you switch to another). The Depth control provides subtle to sub-aquatic levels of modulation.

Chorus 1 produces a sweet, shimmering, slightly metallic sound that is quite musical. Depth is preset to what EH considers "optimal" (the Depth control is inactive), and adjusting the Rate control affects both modulation frequency and delay time, yielding comb-filter and flanger-type sounds in the first half of its range, and wider, more traditional chorus effects in the second half. Chorus 2 produces a considerably more delayed and therefore wider effect, which can get seriously syrupy as you increase the Depth (I got a "Wild Honey Pie"-like warble with Rate at two o'clock and Depth maxed). The Vibrato is functional, if relatively unexciting, and it lacks stereo separation.

The Stereo Clone Theory is a nice-sounding chorus pedal with its own distinct personality. Chorus 1 is the most generally useful setting, though Chorus 2 offers some hip specialty sounds, and, ironically, a more convincing "vibrato" than Vibrato. My only real beefs are that Vibrato doesn't operate in stereo, and that the pedal generates audible hiss.

STEREO PULSAR VARIABLE SHAPE TREMOLO

You might think that a pedal with three knobs--two of which are labeled Rate and Depth--would be pretty straightforward. However, in the case of the Pulsar ($110 retail/$82 street), the Rate control begins at medium-slow speed and exceeds recognizable "tremolo" velocity well before reaching the halfway point. Even better, the Depth control's usable range lies between ten o'clock--when it kicks in--and two o'clock, beyond which it begins to "warp by modulating between positive and negative phase," resulting in ring-mod-like weirdness.