Split-Phase Bucket Brigade Delay Line

While digital audio processors are often plagued by latency issues, analogue circuits are known for their instant response. But what if you want to delay a signal on purpose, without the use of tape or digital memory? Enter the bucket brigade delay (BBD) line: a series of capacitor ‘buckets’, which pass the incoming signal along at a high rate in order to delay it.

Delay 1 is a fully analogue BBD-based delay module with a multitude of features geared towards modern musical use. An integrated temperature-compensated, high-frequency voltage controlled oscillator (VCO) provides the ‘clock’ signal necessary to drive the delay line within 1 to 50 ms.

By increasing the drive frequency to over 20 kHz, the classic ‘BBD clock whine’ problem is solved, while still providing a wide range in delay time. Classic chorus, flanger and echo effects are easily achieved using the dry/wet blend, feedback and damping parameters.

To greatly reduce distortion and noise, Delay 1 includes a newly developed control circuit. The improved fidelity is maintained at a multitude of signal levels by an integrated high-performance compander, while maintaining signal dynamics.

The module’s ‘split phase’ topology provides two different dry/wet mixes, which may be used to convert mono signals to stereo, for complementary comb filtering and more.

Delay 1 also allows you to experiment with Karplus-Strong synthesis, an exciting technique to create string and percussion type sounds. This is made easy by an integrated noise transient generator, driven by the ‘pluck’ input, and by the clock VCO’s 1 volt per octave response.

By re-engineering the classic analogue delay line, Delay 1 brings the unique magic of BBDs into the contemporary electronic musician’s arsenal.