Happy Nerding FX-Aid

Resources

CV range

  • CV inputs 1-3 have a range of [0v to +3v]
  • SRR input has a range of [-2v to +5v]
  • D/W input has a range of [-5v to +5v] (positive voltage decreases the wet level, and negative increases dry level)

+/-5 V from mid position, and thus around 10Vpp from full wet or dry.

SRR input has that weird range because it can go much lower in frequency vs up. Positive voltages decrease the sample rate, because that is what most of the users like to do.

D/W moves from Wet to Dry with positive CV voltage, and from Dry to Wet with negative voltage.

CV1-3 inputs are limited to only 3.3V because some gate signals are only 4V, and attenuators are much more spread than amplifiers.

0V applied to the Sample Rate does not change the default rate.

CV assignment is stored with each preset.

Target signal levels (if your effect starts to clip / crackle / glitches you should attenuate the inputs)

FX AID's input should not exceed -7V...+7 V, which is a wise compromise.

FX AID's output is limited to -6V...+6V, which is also a wise compromise, so dry and wet mix is never above 10 V.

FX AID's output is deliberately limited it to 10V vs 12 V, because some other modules can be following FX AID, and they are not obliged to use rail to rail parts to be safe from nasty distortion.

FX AID has a 3dB Dry/Wet mixing law to avoid level drop at 50/50 mixing.

SSR input (bricks) / chip clock

You reduced the sample rate way too much, so the chip became non-responsible on such a low frequency.

Please do not exceed +5V for lowering the sample rate and minus 2V for increasing it.

Some words regarding the update process (levels / if it stucks)

I’m able to reliably update FX AIDs with levels from -1.2V..+1.2V down to -0.1V…+0.1V.

If FX AID was interrupted during the update and becomes irresponsible and no lights are active: switch off the case power, press both buttons and while they are still pressed switch on the power. FX AID will reboot to firmware update mode with two inner leds blinking asking for the proper update.

Alternative ways to navigate

As requested now there are two possible ways to navigate the effects:

  1. standard browsing with sequential selection in both left and right directions
  2. new browsing option with left button selecting 1 of 4 banks and right button selecting 1 of 8 effects within this bank.

Delay

"Delay Sync" has "Divider" control to set the desired ratios of the incoming clock.

"Delay Tap Tempo" do not need this control, as it should follow the tapped time. It can also be used with ordinary clocks and "Tone" control can be adjusted to the asked HighPass in the feedback.

Misc

List of SpinASM code for guitar effects pedals and other applications : https://mstratman.github.io/fv1-programs/

http://spinsemi.com/products.html

https://github.com/HolyCityAudio/SpinCAD-Designer : SpinCAD Designer is an open source Java project which allows creation and audio simulation of patches for the Spin FV-1 audio DSP chip