Dave Smith Instruments Evolver Operation Manual page 12

Chaining Mono Evolvers
You can also use one or more mono desktop Evolvers for more voices. If using one,
set the Keyboard to MIDI clock Out, and set Poly Chain to 2. Set the Evolver to MIDI
Clock In.
A Note on Versions
The same basic voice structure is used on all Evolvers. Great care has been taken to
maintain backwards compatibility, but there have been a few changes necessary in
both the mono Evolver and the Poly Rack to make them work more seamlessly with
the keyboard.
As a result, you may have to update your current synths to be compatible. Please
check our website to get the latest information on these updates.
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