MOS Subcommander mods ??

[StephenGiles]

My understanding of the Subcommander A/R generator circuit is that when energised by an input signal, the Q output of U7-A goes high - presumably to the same voltage whatever the strength of the input signal. How can the voltage at the Q output be made to vary with the strength of the input signal, so that the filter sweep peak is player controlled?

Presumably the existing envelope circuit always peaks at the same point when triggered irrespective of how hard the notes are played - not always ideal!

Ah, a decent wifi signal in the VIP lounge at Alicante airport! Our hotel room was on the 6 floor so we had a very poor signal.

The usual envelope follower controlled type of VCF is in my opinion quite useless because of the ripple in the decay portion of the sweep, causing a bubbling effect - although I am aware that some folks like that!

The solution to my idea may not be simple of course.

[slacker]

When the circuit is triggered the Q output goes high and starts charging the cap (C35) through the attack pot, the voltage rises until the output reaches the voltage set by R58 and R59 at which point U8-B switches causing Q to go low starting the decay part of the envelope.
So in theory changing the voltage on pin 6 of U8-B changes the peak voltage.............

[StephenGiles]

When the circuit is triggered the Q output goes high and starts charging the cap (C35) through the attack pot, the voltage rises until the output reaches the voltage set by R58 and R59 at which point U8-B switches causing Q to go low starting the decay part of the envelope.
So in theory changing the voltage on pin 6 of U8-B changes the peak voltage.............

You know I read through that circuit description maybe 20 times whilst on holiday recently, but never cottoned on to that - many thanks, I'll try putting the voltage at C7 (buffered) on pin 6 of U8-B and see what happens.