> I've just noticed that my A156 Quantizer is about a semitone out of
> tune. I tuned my VCOs against my Midi synth but when I play the 155
> through the Quantizer, the notes are out. Which of the four trimmers
> should I attack (the scale is bang on one octave, it is just the offset).

The small multiturn trimming potentiometer P4/1k (next to the voltage
reference IC6/TL431, looks like a transistor) is used for the output
scaling. The easiest way is to set the quantizer to quint quantization so
that only 2 voltag jumps within one octave occur.

>
> Yours Aye
>
> Stuadh
>
> PS still interested in how to have the quantizer play the 4th instead of

the 6th.

We can modify the A-156 firmware if you are willing to pay for the working
time required to change the software. Please get back to me directly for
details.

Best wishes
Dieter Doepfer