THERE ARE 2 IMPORTANT DIFFERENCES IN THE CMS 1045 COMPARED TO THE ORIGINAL ARP 1045.

THE LOWER TRIGGER INPUT (MATRIX SWITCH #7) HAS BEEN REPLACED WITH A DEDICATED FILTER AUDIO INPUT. INDIVIDUAL TRIGGER INPUTS TO THE ENVELOPE GENERATORS ARE STILL AVAILABLE AT THE UPPER MATRIX SWITCHES.

THE VCO ENABLE SWITCH HAS BEEN REPLACED BY A FILTER AUDIO INPUT SELECTOR SWITCH THAT ENABLES THE USER TO SELECT BETWEEN THE INTERNAL VCO AND THE EXTERNAL AUDIO INPUT. THE ADJACENT LED GLOWS RED WHEN THE SELECTOR SWITCH IS SET TO "INT" AND GREEN WHEN SET TO "EXT".

WITH THE SELECTOR SWITCH SET TO "INTERNAL" THE MODULE BEHAVES EXACTLY LIKE THE ORIGINAL ARP 1045. EXTERNAL WAVEFORMS (WITH A 1K OHM OUTPUT IMPEDANCE) CAN BE SUMMED WITH THE INTERNAL VCO AT LOWER MATRIX SWITCH #3 AND SENT TO THE FILTER. THE INTERNAL VCO CAN STILL BE SWITCHED OFF BY MOVING THE WAVEFORM SELECTOR SWITCH TO OFF (NO WAVEFORM SYMBOL) OR SETTING THE SELECTOR SWITCH TO "EXTERNAL". THE VCO DIRECT OUTPUT IS ALSO AVAILABLE AT LOWER MATRIX SWITCH #3.

WITH THE SELECTOR SWITCH SET TO "EXTERNAL" THE EXTERNAL AUDIO INPUT (LOWER MATRIX SWITCH #7) IS FED TO THE FILTER AUDIO INPUT. THIS ENABLES MORE COMPLEX PATCHES TO BE REALIZED SUCH AS USING THE 1047 MULTIMODE FILTER IN SERIES WITH THE 24Db LOWPASS LADDER FILTER IN THE CMS 1045. THIS IS NOT POSSIBLE WITH THE ORIGINAL ARP 1045 MODULE BECAUSE THE INTERNAL VCO IS HARDWIRED TO THE FILTER AUDIO INPUT.