OVERRIDING M.I.D.I.

Llyal Gordon frans at CCIT.ARIZONA.EDU
Mon Jan 27 04:11:02 CET 1997


> For my application, MIDI bandwidth is a problem. I want to use instruments
> on the market that communicate by MIDI- but the ways i want to control the
> instrument overload MIDI's abilities. I seem to ask too much from the
> machine. I don't think so.


I want to control gear such as the EVENTIDE processors, digital EQs (such
as made by BEHRINGER), sound modules of all types, like the NORD LEAD and
the KORG PROPHECY. Given a MIDI equipped synth, i may send it 10 notes to
play plus maybe 25 different control msgs affecting the sound parameters
(pitch, resonance, etcetera).  In this example, the synth is suppose to
play a chord, while the 25 parameters continuously change for however long
the sound lasts (like a very complex ADSR/filter envelope). A MIDI synth
cannot do this. In fact, just playing the chord alone, expecting all notes
to sound at once, can be a problem for MIDI synths. Even the sound i might
hear won't be in synch (instantaneous) with my pressing of a key. 

I realize this is not a new problem for MIDI gear. I do, however, want to 
find a solution. To me, it is not practical to build gear that already 
exists, just so i can implement more control over it. I confess, i rather 
play music than build the instrument i play. But if the instrument 
doesn't exist, what does one do?

Basically, i want to have the ability to change every single changeable 
parameter on a piece of MIDI gear at any given instant. NO DELAY. IF I 
change 256 parameters at a given event, i don't expect 256 events to 
pass before i realize all the changes. I need REAL-TIME CONTROL. This is 
the ideal.

>From what i understand about MIDI, an UART is used. This is attached to
some sort of registers, DMA, I/O, etcetera, of the instrument itself- is
this correct? Now, can a computer just dump data at this point (bypassing
MIDI), to the device, as fast as the device can handle it? (What kind of
synching or timing do i need to worry about?) 

My logic goes as follows- MIDI is serial in how it transfers data. A
parallel version (if built) would be a magnitude or so better in speed. 
Hell, just bypass the "MIDI" interface and tap directly into the I/O
circuitry of the instrument. That would be as fast as it could get. 


Why don't i just do it, you ask? I know "some" electronics. Not much. 
That is why i opt NOT to build my own instruments. I might build this 
"MIDI-override" if i know more of what is involved, what results i could 
expect, and just the feasibility of implementation. I currently stick with
analog instruments (acoustic drums and electric guitar) because you just
cannot beat the real-time control of their sound. If i did this "bypass of
MIDI" to synths, could i realize the control over sound that i receive
from the acoustic drums and electric guitar (or even analog synth)? 

I ask- can it be done? Can i buy a MIDI-equipped device off the shelf, do 
some straightforward modification to bypass the MIDI, and get results? 

What solutions or advice do YOU have to offer?

I appreciate all the help i can get!


Llyal Gordon
SUBVOX, tucson AZ
frans at ccit.arizona.edu







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