October 2006

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Guyatone Optical Series

By Michael Ross

With the sounds of electronica seeping steadily into all forms of music these days, auto way and tremolo pedals are increasingly popular, whether they’re trying to emulate computer-generated tones or going for that Radiohead vibe. Two new pedals from Guyatone, the Optical Series Ultron and Ultrem, explore the outer limits of these popular sounds.

Housed in a heavy-duty but lightweight Hammond chassis, these pedals share a large proportion of their specs and features. Both offer 100 percent analog audio paths based around custom-made photocouplers. Many of the audio control parameters are similar and easily adjustable from the units’ front panels, requiring no menu scrolling. Each model contains a CPU, featuring a digital oscillator with six selectable waveforms whose rate is controllable via tap tempo or the manual speed control. Rate can be displayed in beats per minute (bpm) or milliseconds, for accurate syncing to song tempos. Several effect parameters may be assigned to an optional CV controller (expression) pedal for real-time manual adjustment.

LAYOUT
At first glance, the Optical Series pedals seem daunting: so many switches and knobs. Fear not – there’s much fun to be had with nary a glance at the manual, though each pedal reveals even more features once you start reading those slightly arcane tomes. Both pedals have mono inputs, while the Ultrem provides stereo outputs for pan effects. Each sports solid-feeling switches: a true-bypass on/off switch, a second footswitch that doubles as a tap tempo, and a control switch to alter function settings. A small push/pull knob sets the speed on each unit, while a second selects the mode and waveform. A three-way mini-toggle sets the tap relationship (1:1, 2:1, or 4:1). By using these small knobs and switches in various combinations, you give yourself options aplenty.

ULTRON
The Ultron circuitry is based on the vintage Mutron III envelope filter. Three types of filter effects are available: Envelope Filter (effect controlled by pick attack), Auto Wah (controlled by internal oscillator), or Manual Wah (controlled via an external expression pedal). Frequency range, direction, and filter intensity for all three effect types are adjustable via the Threshold, Frequency, Drive, and Peak controls on the unit’s front panel. Ultron offers six effect modes, as well as some sub-modes that can be accessed by pressing the control footswitch. These modes include Momentary Wave – which functions as an envelope filter until the control footswitch is pressed and held, then switches to an auto wah – and WaveTap, an oscillator-controlled auto wah with its rate determined by the tap tempo function. Four other modes employ an optional expression pedal. Pedal Wah functions like a standard wah, Pedal Depth varies the frequency depth, and two Pedal Speed modes vary the speed over different ranges. Stepping on the Control/Tap tempo switch quickly converts these last four back to standard envelope filter mode. You can select the type of oscillation for any of the auto wah modes, choosing between triangle, sawtooth, and square waves. The Ultron also features high pass, band pass, low pass and notch filter settings. These are the basic controls and features, but the unit offers much, much more for fine-tuning both tone and tempo, as well as additional effect options.

ULTREM
At last – tap tempo tremolo available in a pedal form! In addition to being able to match your tremolo speed to a song’s tempo in live situations, the Ultrem can emulate various vintage and current tremolo units, or create all-new sounds, through its selection of waveforms. Sporting many functions and controls similar to Ultron, Ultrem adds Speed, Depth, Saturation (for tube-style warmth), switchable dry blend, stereo panning, and expression pedal control of tremolo rate or depth. An expression pedal can also be used as a volume pedal or manual amp panner.

SOUNDS
The sounds available in these two pedals can be summed up in one word – terrific! The analog optical circuitry combines with the high-end components to provide exceptional depth and warmth. Whether employing the Ultron for Sly-type funk-driven single-note excursions or analog synth-style rhythmic auto wah effects, or kicking in the Ultrem for spaghetti-western warble or wide-screen stereo pan effects, these exceptional pedals deliver an aural feast as sumptuous as the backstage catering at a Stones concert.

ARE THEY FOR YOU?
If you’re a casual user of these types of effects, there are plenty of smaller, cheaper units on the market. But if you’re serious about filtering or tremolo, there’s nothing out there in pedal form that beats the Ultron or Ultrem for spectacular sound and range of creative control.