Pitch Bend Wheel fake 14 bit resolution

[Impostor]

It doesn't matter much to me, but I found out that while pitch bend messages "should be" 14 bits instead of the usual 7 bits for CC, resulting in 16.384 discrete values, my midi keyboard's pitch wheel sends those values with increments of 128, so the actual resolution of the pitch bend wheel is just 7 bits after all!

Nowhere in the documentation of my midi keyboard can I find information about it. So I wonder, if one were in the market for a midi keyboard with an actual 14 bit pitch wheel resolution, how would one find it?

Related question: the pitch wheel is not really useful for smooth high resolution live automation of other parameters than pitch because of the wheel spring. Are there midi controllers with smooth wheels or faders which do have 14 bit resolution?

[folderol]

That's a bit crap! Mine varies between 50 in the centre to 80 at the extremes (prolly done to mask pot noise).
I'd guess your best bet is to get an external controller with long sliders. My BCF2000 seems to do quite well, and the controls are configurable.

[Impostor]

That's a bit crap! Mine varies between 50 in the centre to 80 at the extremes (prolly done to mask pot noise).

Well, that's not exactly stellar either :)
Still a far cry from 14 bits!

[folderol]

That's a bit crap! Mine varies between 50 in the centre to 80 at the extremes (prolly done to mask pot noise).

Well, that's not exactly stellar either
Still a far cry from 14 bits!

You're quite right, but that's only on an elderly Midicontrol 49.
The sliders on the BCF2000 (when configured as 16 bit) have a (very variable) LSB of around 30

[bluebell]

My M-Audio Code61 is even worse:

Code: Select all

hm@bubu:~$ aseqdump -p 20
Waiting for data. Press Ctrl+C to end.
Source  Event                  Ch  Data
 20:0   Pitch bend              0, value 384
 20:0   Pitch bend              0, value 640
 20:0   Pitch bend              0, value 768
 20:0   Pitch bend              0, value 1024
 20:0   Pitch bend              0, value 1280
 20:0   Pitch bend              0, value 1408
 20:0   Pitch bend              0, value 1664
 20:0   Pitch bend              0, value 1792
 20:0   Pitch bend              0, value 2048
 20:0   Pitch bend              0, value 2176
 20:0   Pitch bend              0, value 2432
 20:0   Pitch bend              0, value 2560
 20:0   Pitch bend              0, value 2816
 20:0   Pitch bend              0, value 3072
 20:0   Pitch bend              0, value 3200
 20:0   Pitch bend              0, value 3456
 20:0   Pitch bend              0, value 3584

[Impostor]

My M-Audio Code61 is even worse:

Code: Select all

hm@bubu:~$ aseqdump -p 20
Waiting for data. Press Ctrl+C to end.
Source  Event                  Ch  Data
 20:0   Pitch bend              0, value 384
 20:0   Pitch bend              0, value 640
 20:0   Pitch bend              0, value 768
 20:0   Pitch bend              0, value 1024
 20:0   Pitch bend              0, value 1280
 20:0   Pitch bend              0, value 1408
 20:0   Pitch bend              0, value 1664
 20:0   Pitch bend              0, value 1792
 20:0   Pitch bend              0, value 2048
 20:0   Pitch bend              0, value 2176
 20:0   Pitch bend              0, value 2432
 20:0   Pitch bend              0, value 2560
 20:0   Pitch bend              0, value 2816
 20:0   Pitch bend              0, value 3072
 20:0   Pitch bend              0, value 3200
 20:0   Pitch bend              0, value 3456
 20:0   Pitch bend              0, value 3584

All multiples of 128. If you move the wheel more slowly you'll probably (at best) get 128 increments, like my M-Audio 49 MK3.

[Linuxmusician01]

It doesn't matter much to me, but I found out that while pitch bend messages "should be" 14 bits instead of the usual 7 bits for CC, resulting in 16.384 discrete values, my midi keyboard's pitch wheel sends those values with increments of 128, so the actual resolution of the pitch bend wheel is just 7 bits after all!

Nowhere in the documentation of my midi keyboard can I find information about it. So I wonder, if one were in the market for a midi keyboard with an actual 14 bit pitch wheel resolution, how would one find it?

Related question: the pitch wheel is not really useful for smooth high resolution live automation of other parameters than pitch because of the wheel spring. Are there midi controllers with smooth wheels or faders which do have 14 bit resolution?

Bloody hell! Now I understand why some of my synths work well w/ the mod & pitch wheels ofcertain Midi keyboards and some don't! Thanks for the info!

Example when I turn the mod wheel of the wretched keyboard as slowly as I can from 0 to max:

Code: Select all

$ aseqdump -p 24
Waiting for data. Press Ctrl+C to end.
Source  Event                  Ch  Data
 24:0   Control change          0, controller 1, value 2
 24:0   Control change          0, controller 1, value 6
 24:0   Control change          0, controller 1, value 10
 24:0   Control change          0, controller 1, value 14
 24:0   Control change          0, controller 1, value 18
.
.
.
 24:0   Control change          0, controller 1, value 127

Example when I push the pitch wheel up from neutral to max:

Code: Select all

$ aseqdump -p 24
Waiting for data. Press Ctrl+C to end.
Source  Event                  Ch  Data
 24:0   Pitch bend              0, value 0
 24:0   Pitch bend              0, value 128
 24:0   Pitch bend              0, value 704
 24:0   Pitch bend              0, value 1344
 24:0   Pitch bend              0, value 1920
 24:0   Pitch bend              0, value 2560
 24:0   Pitch bend              0, value 3136
 24:0   Pitch bend              0, value 3712
 24:0   Pitch bend              0, value 4352
 24:0   Pitch bend              0, value 4928
 24:0   Pitch bend              0, value 5568
 24:0   Pitch bend              0, value 6144
 24:0   Pitch bend              0, value 6720
 24:0   Pitch bend              0, value 7360
 24:0   Pitch bend              0, value 7936
 24:0   Pitch bend              0, value 8191
 24:0   Pitch bend              0, value 8000

As you can see the max. mod value is 127 (7 bit) instead of 16.384 (14 bit). And like you described: the pitch wheel goes up in steps of 128 (to 8.000), which indeed is 16.000 from min to max but in a resolution of 7 bit instead of 14 bit. Darn it!

On some synths this results in my hearing not a "glide" from the pitch wheel, but I can hear the synth jump from note to note. I.e. in discrete steps (of 128) instead of a continuous glide up/down. This is on synths that are (hard) configured to go up 2 octaves from the pitch wheel. Synths that do not go up such a large amount of notes/octaves work better w/ the same keyboard.

I couldn't work out what the bloody problem was w/ the same keyboard acting like a piece of sh*te with one synth and working fine w/ another. It's the cheep keyboard, not the synth!

[folderol]

The problem is largely physical.
Consider the actual track length of an average rotary control against the contact area of the wiper, then add in irregularities in the surface plus background noise - added to micro-movements caused, or amplified by vibration of the control wheel.
The 'cheap' way to sort-of fix that is to reduce the resolution (and hope nobody notices).
Compare that to a 100mm good quality slider.
Lastly compare either of these to a numerically calculated value.

[Impostor]

Example when I turn the mod wheel of the wretched keyboard as slowly as I can from 0 to max:

Code: Select all

$ aseqdump -p 24
Waiting for data. Press Ctrl+C to end.
Source  Event                  Ch  Data
 24:0   Control change          0, controller 1, value 2
 24:0   Control change          0, controller 1, value 6
 24:0   Control change          0, controller 1, value 10
 24:0   Control change          0, controller 1, value 14
 24:0   Control change          0, controller 1, value 18

Hmm, that makes my keyboard's modwheel performance quite impressive: I have to move it really fast to make it skip steps.

[Linuxmusician01]

The problem is largely physical.
Consider the actual track length of an average rotary control against the contact area of the wiper, then add in irregularities in the surface plus background noise - added to micro-movements caused, or amplified by vibration of the control wheel.
The 'cheap' way to sort-of fix that is to reduce the resolution (and hope nobody notices).
Compare that to a 100mm good quality slider.
Lastly compare either of these to a numerically calculated value.

Indeed. I don't notice that the pitch wheel of my crappy cheap Midi keyboard has a "resolution" of only 7 bit if I use it on a synth that only goes up a few notes by bending. However, when I use it on one that wants to "bend" a notes a lot w/ the wheel (an octave or more) then it's like legato (going with your fingernails over the keys of a piano from one note to another). I hear the notes jump from note to note. Like something's broken in the mod wheel. When I use one of my other Midi keyboards on the same synth the "problem" is gone.

Anyway, I think it's very "unfortunate" that manufacturers aren't clear about the "resolution" (7 or 14 bit) used on their mod and pitch wheel.