[sdiy] Midi CC update rate question

[Colin f]

> If I am designing a product with 5 knobs capable of sending 
> MIDI CC data when they are adjusted what is a sensible update 
> rate for their transmission over MIDI?
 
> For example, if only one control is continuously turned the 
> product could theoretically transmit CC messages at an update 
> rate of about 1562 per sec if running status was used!  

Assuming 128 steps of rotation, 1562Hz is enough to capture you turning the
knob back and forth over its full range 6 times per second.
Do you want to give that a try ?

> Do you think it is reasonable to 
> cap the maximum update rate at about 100Hz for a single CC 
> transmitted over MIDI?  This would not hog too much MIDI 
> bandwidth and provide plenty of space for merging in other MIDI data.

I find 100Hz about right.
It depends on how the attached instrument responds to the data.
If it has some kind of smoothing of CCs, you can get away with a lower rate.

> Now if there are 5 knobs on the product and all were being 
> manipulated simultaneously, do you think each controller 
> should send CC data 100 times per second, for a total of 500 
> CC messages per sec?

If you've got 2.5 people with a hand on a knob each, I don't think anyone's
going to know if their knobs aren't quite responding as well as they did
alone, in the general melee.

Cheers,
Colin