EM-601 | Analog BBD Reverb & Echo

TECHNICOLOR is a bucket-brigade reverberation and echo processor built around a specialized 3328-stage, six-tap BBD architecture. Two selectable signal paths provide distinct temporal responses, combining multi-tap reverberation, variable delay, regenerative feedback, and voltage-controlled time modulation within a single instrument.

In CONCURRENT mode, the incoming signal is distributed across six simultaneous BBD terminal taps, producing a composite reverberation structure with overlapping reflections and diffuse spatial character. Switching to DISCRETE mode routes the signal through the full 3328-stage delay line, providing echo times from approximately 20 to 250 milliseconds.

The Clock Frequency control governs delay time across both operating modes. Independent Fixed and Variable CV inputs permit external modulation of the BBD clock, with a bipolar attenuverter providing adjustable depth and polarity for the Variable input. Slow modulation introduces chorus and ensemble-like movement, while higher modulation rates produce vibrato, pitch displacement, and more complex time-domain effects.

A dedicated filtering network suppresses clock-related artifacts inherent to bucket-brigade operation, maintaining signal clarity across the available timing range. Feedback / Repeats controls regeneration through the delay network, extending from isolated reflections to sustained repetitions and self-oscillation.

The Blend circuit provides continuous adjustment between the unprocessed input and the BBD signal, with an independent CV input for voltage-controlled dry/wet modulation. Input Level offers direct control over the signal entering the processor, accompanied by an overload indicator for monitoring signal amplitude.

01 / DELAY ARCHITECTURE

3328-stage, six-tap bucket-brigade architecture
CONCURRENT six-tap reverberation and DISCRETE delay modes
Delay time — approximately 20–300 ms in DISCRETE mode
Clock-noise suppression filtering network

02 / CLOCK & MODULATION

Variable BBD clock frequency
Independent Fixed and Variable time-modulation CV inputs
Bipolar modulation attenuverter
Chorus, vibrato, and pitch-modulation capabilities

03 / FEEDBACK & SIGNAL CONTROL

Regenerative feedback with self-oscillation
Voltage-controlled dry/wet Blend
Adjustable input level with overload indication

POWER & CONNECTIVITY

± 12 V. 10-Pin IDC / Keyed Headers. Red Stripe: − 12 V.

LA CIRCUITS, INC.

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