Wersi CX-1 – 19″ Drumexpander

Wersi CX-1 drum part in 19″ case

Starting point was – as so often – an ebay finding … three PCBs from a Wersi CX-1 auto accompaniment. One needed to be populated.


Case recycling

The PCBs needed to be put into the case of a non functional stereo limiter. It’s PCB was ripped out – the rest was reused like the power supply, frontpanel LEDs and switches, audio jacks and the frontpanel itself.



The Wersi pcbs are very well layed out and documented. After populating the 3rd one they all received dedicated connections for power supply, Trigger input and stereo audio output.


Central point

Everything comes together in a central PCB distributing the power supplies and holding a stereo summing mixer.


Front panel

Well, this surely will not win a design price – at least it’s made of recycled parts and quite functional.


Modding and the magical SYNTHEDRUM

The individual sounds of the CX-1 are harmonizing quite well, i did not want to change much. The BD was a bit waek and i could improve it with another capacitor. The mysterious voice called “Synthedrum” is similar to a typical simmons Piuuuu (without noise or 2nd oscillator though). It can be easily modded in decay length, pitch and Envelope depth.



Another musik video where i used the 19″ CX-1.