This is the warm and glorious BBD-type chorus featured in numerous classic Roland and Boss instruments and effects unit. By "BBD," we're not talking about 90s R&B superstars, "Bell Biv Devoe"- BBD refers to the "bucket-brigade device," analog chips introduced in the 70s. "Bucket-brigade" refers to the concept of extinguishing distant fires by transferring water via many, many buckets. The analog bucket-brigade delay chips worked on a similar principle - these chips had many tiny capacitors that temporarily stored fragments of audio signals which were moved through each capacitor "stage" at an interval determined by an external clock frequency. The frequency of the clock determined how fast the signal moved through the stages, corresponding to the overall delay time. Much like a sloshing water down the line through numerous buckets, the signal emerging at the end of the line was a little compromised from the initial signal, and the resultant audio lost some high- and low-frequency content. This unintended side effect actually sounded great for flanging, chorus, and delay effects. In addition to frequency loss, sound got a little distorted in the process, giving a little extra personality. For these reasons, BBD-based effects are still prized.
In Stereo, Where Available
The chorus effect featured in original Roland Space echo units was a strictly mono affair - that is, there was one BBD processor, with the dry signal mixed with effected signal. Pseudo-stereo (that's a nice way of saying "fake") could be achieved by routing the dry and wet jacks to separate amplification channels.
Setting Stardust 201's Stereo/Mono toggle to the Mono position works as above - a single one-BBD effect, mixed with the dry signal in mono. When the Stereo/Mono toggle is in Stereo position, Stardust applies two independent (and phase-inverted) chorus effects for true stereo, at no extra charge (you're welcome).
On/Off (white button)- Enables and disables the chorus effect.
Rate- Sets the chorus internal LFO speed from 0.10 to 0.53 Hz.
Intensity- Sets the effect depth, i.e. the amount of delay time mod.