[sdiy] Ring modulator and power supply questions

[Rutger Vlek]

Hello everyone,

i'm building an analog synth containing a version of the SBM RingModulator 
(http://www.ele4music.com/pdfs/sbm.pdf). I'm running it on 15V instead of 
12V and it works fine except that the input's have to be very high to get 
the thing working! Plugging the VCO's into it doesn't work, but boosting 
them through a mixer first does work. What is the simplest way to get the 
input threshold of the RingMod down or the inputsignal up in volume? I'm 
using the latest Oakley VCO's.

Another question is about power supply. I run my synth on 15V but i have a 
keyboard i want to build in that runs on 12V (originally it was an Evolution 
MK149). What is the simplest way to convert the 15V to 12V? Does someone now 
a circuit that can do this? Or can the Evolution handle the 15V?

Regards,

Rutger