EXAMPLE Expression Pedal/Pot Speed

[finebyfine]

I'm working on an fv-1 one-off that is going to use an expressional pedal and had been a little anxious about the tracking speed being too slow because of the stability filters on the pots.

Here's a thread on the spin forums describing how to use a highpass filter to counteract the lowpass filter on the pots.

Code below is from user Don Stavely and reposted due to the often ephemeral nature of forums:

equ   potfilt   reg0
equ   fastpot reg1  

rdax    pot0, 1
rdfx    potfilt, 0.001    ; this is the shelving highpass filter
wrhx    potfilt, -0.75    ; it cuts lower freqs by factor of 4
rdax    fastpot, 0.75     ; this gives 4X recursive gain
wrax    fastpot, 1        ; to recover full range

 

[fig]

If I read this correctly, then this is a replacement definition for the pot, and you'd call this rather than the default definition?

 

[Robert]

Basically yes. Where you would normally retrieve the pot value by loading it into the accumulator with:
rdax pot0, 1

You would now use the fastpot register instead (after the above code has been executed).

This is also built into SpinCAD, if you open the Options dialog for the Pot block there is a "Speed up" checkbox.

 

[finebyfine]

Basically yes. Where you would normally retrieve the pot value by loading it into the accumulator with:
rdax pot0, 1

You would now use the fastpot register instead (after the above code has been executed).

This is also built into SpinCAD, if you open the Options dialog for the Pot block there is a "Speed up" checkbox.

Lmao I'm kicking myself for how simple that is in SpinCAD, but in my defense I understand why I missed it. (Can't resize the control window, but CAN check the box)