Dynacord CLS 222

The Moog Minitaur Soprano

This rotary speaker effect, vulgo Leslie®, was built by the german company Dynacord from late (?) 1988 till 2003. It was built in a white and a black version. Its predecessor was the CLS 22 form 1982. The newer got a third stereo wide setting on the the front panel and an additional Mono Out socket on the back. And some capacitors at the outputs were dropped on the newer revision according to the schematics. But they are found soldered onto the sockets of my CLS 222 unit. So the CLS 22 and the newer CLS 222 might be in fact identically, besides the additional mono output socket just found on the newer CSL 222 version.
And although you might find some text about the CSL 222 using digital technique, it is an all analog schematic. So this might be just just referring to "digital" as it was the buzz word of the eighties.

Due to the splitting of the ingoing signal in bass and treble, sending each of these into two BBD lines (so 4 BBDs in total), and these the volume and the panning being modulated by one LFO for the bass and another for the treble gets the sound very close to the real thing. Of cause there is a ramping up and down when switching the speeds.
Both versions don't add distortion often heard when using rotary speakers, so you might need to add this using a different FX.

The BBDs are four TDA 1022 chips.

The frequency or period of the LFOs are set according to the schematics to these values:

There are XLR outputs in addition to the 1/4" sockets, but the XLRs are not balanced. The additional stereo TRS output is able to drive a headphone.