MIDI Swell Pedal issue

Hi there,

I’m having trouble making the second of my two swell expression pedal work.

They are both part of the same MIDI unit.

The ‘Swell’ pedal works as expected, but it is the ‘Solo’ pedal (for use with Salisbury) with which I am having issues.

I use MIDI-OX as a test bed. Both pedals are sending MIDI signals through successfully, and I have adjusted the angle of the potentiometers so that they act in the way they should.

It is something to do with the MIDI signals that are being received which differs between each pedal.

In MIDI-OX’s Input monitor, the ‘Swell’ pedal gives numbers between 50-68 in each particular stage of travel in the ‘CHAN 2’ column. With the ‘Solo’ swell pedal, it only gives the same ‘7C’ reading for each stage, with the only thing changing being the timestamp. This leads me to think that the signals being sent are being received in the wrong format.

The fact that any signals are being received at all proves that nothing electrical is going wrong - HW also picks up the control via Auto-Detect. The pedal does not however open or close the solo box as desired.

Any help would be hugely appreciated!

Many thanks,

Joseph

[mdyde]

Hello Joseph,

For a MIDI control change message the third byte needs to be the 'value', which should vary according to the position of the pedal (ideally from near-0 when the pedal is 'fully closed' to near-127 [decimal, =0x7f hex] when 'fully open'):

https://www.midi.org/specifications-old ... di-message

If not, your circuitry or MIDI encoder isn't working properly somewhere.

What MIDI controller are you using?

It sounds like the issue is in your midi controller. You should be seeing a range of numbers from the continuous controllers' output of 0-127 or within +/- 1 of that range. The controller port for your swell pedal appears to be misconfigured. Does your controller have internal calibrate functionality to match the input resistance range from the pedal mechanism to the appropriate CC output range (0-127)?

You may also want to look at how you have the mechanical adjustments on your pedals set. The small range of output values from your controller may indicate you are getting only a narrow range of rotation of the pot on your pedal mechanism.

Thanks both for your help.

I have resolved the issue of sorts! It was to do with orientation of the pot.

It’s not perfect, but it is definitely now usable which was the aim.

All best!

[mdyde]

Thanks, Joseph. Excellent.