Pitch Bender Question

[lfo2vcoParticipant Topics: 23Replies: 145Total: 168★★]

Hi,

I am working to emulate the output of a Kiwi-3P pitch Bender using a uiCombo. I have looked through the numerous posts regarding this and have not been able to glen the necessary info to get the result I require. Guidance as always will be very much appreciated.

This is what I need to achieve:

[Pitch wheel] Ch:[ 1] No:[—-] [e0 00 02] // Minimum Value

[Pitch wheel] Ch:[ 1] No:[—-] [e0 00 40] // Middle Value

[Pitch wheel] Ch:[ 1] No:[—-] [e0 00 7f] // Maximum Value

It could be that the minimum value should be 00 rather than 02 and that is caused by a hardware calibration issue.

Thanks in advance for any help on this.
Martin.

[PossemoParticipant Topics: 12Replies: 418Total: 430★★]

I don’t know the Kiwi-3P but in general MIDI pitchbend consists of two 7-bit nibbles making a 14-bit value. So range goes from 0 to 16383 which makes a nice hi-res controller.

Zero is lowest pitch bend
e0 00 00 =>0 => -8192

8192 is no bend
e0 00 40 =>8192 => 0

16383 is highest bend
e0 7f 7f => 16383 => +8191

The structure of the pitchbend message:

first byte: e0 to ef (MIDI channel 1 to 16)
second byte: 00 to 7f less significant bytes (lsb)
third byte: 00 to 7f more significant bytes (msb)

[lfo2vcoParticipant Topics: 23Replies: 145Total: 168★★]

Hi Possemo,

That is a beautifully clear explanation, thank you. I have set the minimum and maximum values on the uiCombo to 0 and 16383 and given it another go and it now works beautifully. I had the minimum and maximum set to 0 and 127.

I guess that the Kiwi-3P does not transmit the lsb part of the message is just an anomaly in the firmware or something.

By the way the Kiwi-3P is the KiwiTechnics upgrade to the Roland JX-3P, basically a complete processor swap out and replacement of some other components. Check it out here and some of Murray’s other upgrades too: https://kiwitechnics.com/jx3pupgrade.htm

[Author]

Posts