slew/unslew filter mod.

When high frequency controlled voltages are applied to the unmodified Synthi filter they are low-pass filtered by the C31 capacitor. This means that the filter will not respond to high frequency CVs, and respond slowly to rapid changes in incoming CVs. The switch...

SYNTHI MOD BLOG Expand and preserve your beloved Synthi “Many Synthi users dare not make mods because they’re afraid to depreciate their valuable instrument. Is understandable, but is a pity because the mods wonderfully expand the...

Modified EMS Synthi A

DC shifter/amplifier with inverse switch and preset switch to trapezoid voltage. Extra trigger-circuit with threshold pot. Changed patchboard lines and many more… Check out Sam’s site here!


• Guide to EMS VCS3 & Synthi A/AKS Modifications & Servicing • CV/Gate and Midi Modification for the Synthi