[sdiy] Roland SH-2000 VCO question

Oakley Sound oakleysound at btinternet.com
Wed May 1 09:42:53 CEST 2019


The actual VCO core is based around the SCR Q103. It's a linear VCO with 
the main timing cap C102. I believe the 555 is being used as a 
'semi-fixed' monostable to produce an error CV, courtesy of IC101 pins 
1, 2 & 3, that partly compensates for high frequency tracking droop and 
also allows some control over the overall pitch of the VCO core.

Regarding the ladder filter - only the early ones had the transistor 
ladder, most have the five stage diode ladder. Years ago I converted my 
old SH2000 to a transistor ladder and although, I thought at the time, 
most of the presets sounded better some of them most certainly didn't. 
The flute and bass guitar sounded better with the diode ladder.

Tony

www.oakleysound.com


More information about the Synth-diy mailing list