[linux-audio-dev] a question re: the MIDI spec

[Martijn Sipkema]

> On Fri, 2004-09-10 at 07:49, Martijn Sipkema wrote:
> > >> [...] the USB specification. And it even appears like some vendors
> > >> are (finally!) starting to follow suit:
> > >>
> > >>    http://midiman.com/products/en_us/KeystationPro88-main.html
> > >>
> > >>    - "USB class compliant-no drivers required for
> > >>      Windows XP or Mac OS X"
> > >
> > > M-Audio started following suit only after they hung their engineers
> > > with a USB cable and bought Evolution who had always made
> > > class-compliant devices.
> >  
> > The problem here is that class compliant devices suffer bad timing
> > because they use bulk transfers for MIDI data. The standard for
> > MIDI over FireWire is much better.
> 
> Hmm.. I'm just about to drop $400 on a USB MIDI interface (Edirol
> UM-880), so that's not something I want to hear!
> 
> Is the timing really that bad?  I don't even think a firewire 8x8
> rackmount MIDI interface exists, so my options are kinda limited. :/

Timing is especially bad when there is other data being transferred on
the same USB bus, as is the case with combined audio/midi interfaces.

There are several USB interfaces that don't use the standard
MIDI-over-USB protocol, but I don't think information about these
protocols is available.

Perhaps there are interfaces that support both the standard protocol and
one with better timing...

--ms