[sdiy] MIDI HD

[Neil Johnson]

Martin Klang wrote:
>> And since they support updates through two messages (one for the
>> higher 7 bits and one for the lower 7 bits) I think you can
>> actually get quite a decent update rate as you only need to send
>> the upper bits when the lower bits over/underflow.
>
> How do you imagine this working on the receiving side? Should the
> device wait to see if the second message arrives, thereby introducing
> latency?

I haven't really thought about it, to be honest.  I can think of many 
different ways to minimise the unfortunate splitting of the value, and I 
have a suspicion that there are even more interesting ways to solve the 
problem.  If I ever get round to writing the stack for a synth and 
implement a solution for this then I'll be sure to let you know.

> Or update immediately, causing skipping which might well be worse
> than the stepping it is meant to cure. (if you don't believe me,
> consider a transition from 0x80 to 0x7f - it would first skip to
> either 0x00 or 0xff depending on which byte you sent first)
>
> I'm not aware of this sort of solution ever being implemented. Anyone
> else?

I gather the ribbon controller on the Kurzweil K2500 sends 14-bit 
controller messages which are handled by the internal synth engine as 
well as transmitted on the MIDI OUT.  Perhaps you could email them and 
ask them how they solved it?

> NRPN's look good on paper, but are a pain to work with. As has been
> pointed out there are very few examples out there of devices that
> support 14 bit resolution controllers.

I guess if not many people ask for the more expensive feature then it is 
unlikely manufacturers will implement it.  Polyphonic aftertouch is good 
example of a great feature that is rarely implemented -- I think the 
number of keyboards (synths and controller) that sense it can be counted 
without removing one's socks.  The Yamaha CS-80 is discounted from that 
list since it is not a MIDI synth (ignoring retrofits).

Cheers,
Neil
-- 
Modules and more :: www.cesyg.com
Homepage :: www.njohnson.co.uk ::