Conference napalm::commusic_v1

To the best of my knowledge, Track and Sequence are not MIDI terms,
though they are used to describe some MIDI products.  Channel is a
MIDI term.  Each MIDI message (with minor exceptions) has a 4-bit 
address, called the Channel Number.  A MIDI receiver can be set to
receive on any one channel.  This lets you control up to 16 instruments
with a single cable.

The above is over-simplified, of course.  Some MIDI messages don't have
channel numbers.  These are messages intended for all instruments,
such as MIDI STOP and MIDI START (the real-time messages).  Often
the channel number is implied by omitting the status byte: this is
called "running status".  The channel of the previous message is
assumed.  Some instruments can be set to "Omni On", which causes them
to ignore the channel number and accept any message.  Still others
receive on more than one channel (but not all), and you set the "base"
channel; they receive on base..base+n-1, where n is the number of
channels.

Sorry if this is confusing; the protocol is quite complex, in order to
permit a wide range of implementations, use inexpensive components,
be interchangable, and be fast.

I have heard the term Track used with the MPU-401, to describe its
output buffering scheme.  You can enable up to eight Tracks.  The MPU-401
will request notes from all of the enabled tracks, and send them on its
single MIDI cable.  I've never found a use for the feature; my software
uses just one Track.

The only reference I have to Sequence is Sequencer--a MIDI device which
can record and play back a sequence of MIDI messages.

Hope this helps.
    John Sauter
               

John's reply pretty much covers it. All I can add is that track and sequence
are terms used with specific MIDI compatible products.  On the Roland MSQ-700,
a track is the exact analog of a multitrack recorder"s track - it is a
distinct stream of MIDI data (what I guess I would call a sequence) that
can be dalt with separately.  An MSQ-700 track (it has 8 of them) can have
data on multiple channels, so the tracks and channels are independent.
The multiple tracks allow you build up MIDI sequences piecemeal (e.g.,
by overdubbing, where the MSQ-700 plays one or more tracks while you
record on another one).  It can merge tracks together (but not take them
apart), and time correct tracks.  You can also "chain" tracks together,
up to 78 (? not even close to a power of 2!) instances, so you can structure
a song as track1: basic verse; track2: alternate verse; track3: basic chorus,
track4: alternative chorus; track5: bridge; track6: intro; track7: coda;
the tell the MSQ-700 to play in order (almost said "in sequence") track6,
track1, track1, track3, track2, track5, track4, track1, track1, track4, track6.
THis has the effect of intro, 1st verse, 2nd verse, chorus, 3rd verse (variant)
bridge, chorus (variant), 4th verse, 5th verse, chorus (variant), coda.
Etc.

len.

Thanks - Len, John

	Different companies using the terms 'track' and 'sequence'
is probably at the root of my confusion.

	Southworth's 'Total Music' proudly boasts that it can handle
99 tracks.

	MegaTracks says it has 'unlimited' track capabilities.

	A salesperson at Daddy's told me that one reason for lots
of tracks is for ease of editing.  Even if you are only using one
'voice'(timbre) - i.e. using only one MIDI channel - it is to your
advantage to put - say, 2 trumpets playing a little contrapuntal
section - on different tracks; then, they can be edited independantly
of each other.  Makes sense.

	Question - is anyone driving a DXn with a PC?  Inputting the
notes from the computer, rather than playing a keyboard?  IF SO, are
you able to switch voices (timbres, patches, or whatever they're
called) on a single channel?

	That is, on playback you hear some bells, then some strings,
then something else?  Note that this was NOT accomplished by pushing
a button on the DX.

	If I can do that, then the TX816 starts to sound more interesting
to me.  True, I'm still limited to 8 simultaneous timbres, but it 
could be any 8-timbre subset of the total number of timbres in a
TX module.  Couldn't do the Rite of Spring or Wagner, but with some
clever switching, I could make it SEEM like more than 8 instruments
were playing.

	True?

							- Karl

re: .3--True.  The commands for switching timbres are defined in MIDI,
and the DX7 implements them.  Indeed, as far as I know all MIDI synthesizers
implement them.
    John Sauter

Re .3, .4 - Most sequencers (including PC-based ones) will record "program
changes".  You can either transmit the program change from the keyboard
while playing, or overdub it in later.  I usually do the latter, as the
sequencers I use (Roland MSQ-100 and MSQ-700) give you an 8 beat countdown
before they start the overdub, and any program changes transmitted during
that countdown are squeezed into the moment just before the overdub starts.
Changing programs in the middle of a bar (overdubs on these sequencers can
only start on bar boundaries) requires split second timing, which can be
a pain on some synths - e.g., my Juno 106 has three buttons that affect
program number (group, bank and patch) and pressing any one of them sends
a program change - e.g., if I'm using program A13 and want to change to
B27, pressing group, then bank 2, then patch 7 results in 3 program changes
being sent (and recorded) - B13, B23, then (finally) B27.  I suppose I could
press all three "at the same time", but I suspect the simultaneity of my
fingers is outrun by the keyboard's scanning rate, so I'd still get multiple
program changes albeit much closer together.  Probably not an issue in
practice.

Setting up program changes directly from the computer (rather than recording
them from the keyboard) ought to be a piece of cake, and only one program.
change need be sent to the synth at performance time.  It's this kind of
control over the contents of the MIDI data stream that makes me hunger for
a good PC with good software.

Read the MIDI implementation chart that comes with your synth to confirm
that it receives program changes.  All MIDI compatible synths that I'm aware
of receive program changes, although it may be under the control of an
enable/disable switch or a mode switch (whcih probably controls reception
and inteerpretation of other kinds of MIDI data, e.g., system exclusive).

Some synths may not respond to a program change if a note on is in effect
(i.e., if it's playing).  The MIDIBass is like this.  Other synths will
respond to a program change if a note is being played, but will abort the
played note (not go to the release phase of the envelope, but just stop dead).
Others will continue playing the note with the new program, but may retrigger
the envelope, or continue at the "same place" in the new program's envelope.
Whatever your synth does, it's probably not what you want for a given
situation.  You will have to experiment to find out what your synth does -
I've never seen this aspect of a synth's behaviour documented.  My rule of
thumb - only change programs during rests, or between notes.  This measn
no program changes during legato passages, where note offs overlap note ons.

This is probably more than you wanted to know, huh?

len.

Does the following violate the MIDI standard??

	MacMIDI32 (by Musicworks)

	"Working with Musicworks' MIDIworks and other available software,
the MacMIDI (tm) series of MIDI-to-Macintosh hardware interfaces connects
the Macintosh to synthesizers and other MIDI devices, making possible a
simple-to-use porfessional music system for composing, transcribing,
performing, and recording."

	"MacMIDI32 allows one Macintosh to play up to 32 independent MIDI
channels, which can be assigned to an unlimited number of synthesziers."


	???Doesn't the MIDI spec have a max of 16 channels?  What do
you suppose they are doing here?

							- Karl

My guess is that they're are two MIDI outs, each with its own set of 16
channels.  Remember, there are only 16 channels per wire, but if you can
run separate wires, you can have as many channels altogether as you want.

len.

Two unique MIDI lines makes sense. Sort of like a bridged Ethernet. On the
other hand, maybe it's a misprint/mistake and they meant 32 tracks.

Ted

	I don't think it's a misprint. 

	They have a diagram in their brochure which shows 2 outputs
(labelled A and B).

	I still wonder how existing software would deal with this,
though.  To the best of my knowledge, most extant MIDI software
deals with 16 channels, period.  Maybe their own software makes
use of this feature.

							- Karl

Yes Karl, I would assume their software makes use of both outputs and outputs
MIDI info for tracks 17-32 on the second MIDI OUT plug. You are probably also
correct in assuming that other MIDI software would not make use of the higher
tracks. 

I could be wrong, of course, since I don't have their device.

If I am correct, however, it is interesting to note how this company has
allocated channels to MIDI OUTs.  I also want to use more than one Roland
MPU-401 with my AMIGA since I intend to have more than 16 possible channels
someday and secondarily I want to be able to use another 401 if some number of
tracks less than 16 gives me performance problems. I was concerned about how to
represent more than 16 channels in the software I intend to write.  I was
considering introducing a new concept like 'BOX', or 'GROUP', or 'LINE' to
represent one of n 401s.  So the user would talk about outputting information
to BOX 1 CH 4, or maybe LINE 1 CH 4, but if you make the simplistic assumption
like tracks 1-16 output through the first 401, 17-32 go to the second 401,
etc., the problem goes away.  I like the idea of not inventing any unnecessary
concepts. 

-jim

The MIDI protocol doesn't allow logical channels 17-32, instead their
(MusicWorks) software outputs on channels 1-16 through 2 wires.
I don't quite remember how the consept is presented to the user on the
screen but the idea of chan. 1-16 thru either line#1 or line#2 is not
far from it. I prefer it since talking about channels 1-32 is logically
misleading. (Try adjusting a synth to listen chan 19?).

What to me is even more interesting is that the MusicWorks' or related
MAC-MIDI interface *inputs* from 2 channels. In other words it can 
listen two separate input data streams when recording. Owning this kind
of system sure would solve many of my problems!

Timo Lehtinen

re: .11, .12--I think inventing an additional concept for the
MIDI channels on the second MIDI wire is a good idea.  Even though
inventing additional concepts causes pain for the user, in this case
I think it would be more painful to not invent a new concept, since
the user would have to remember that channels 17-32 are on the
second cable, and can only be received by instruments connected
to the second cable.  I vote for the two-dimensional numbering system
that Jim suggested but rejected in .11, for the reasons stated in .12.
    John Sauter

	I guess I should have asked the obvious earlier -

	Does anyone *have* Musicwork's MacMIDI and/or MIDIworks?

						- Karl

    Now for an even more basic question....
    
    Is all you need a cable between two MIDI instruments, or does one need
    a special interface as well?
    I'm thinking of a CASIO Digital Horn Model H100 to a Casio/Yamaha
    keyboard for example?
    
    Thanks,
    
    Tim

    Just a cable (or two).  A minimal system would hook the cable from the
    MIDI IN of one synth to the MIDI OUT of the other.  If you want to be
    able to control either synth with the other, two cables connecting MIDI
    INs and OUTs.  It still may not work because next you get into the
    issue of configuring each synth to send or respond correctly.  And,
    even in this simple system you have the possibility of causing an
    infinite loop that fills your buffers and trashes your synths if you
    don't get the configurations right.
    
    Steve 

Steve has just covered the worst case, but don't worry.  ALL you need for the
Casio horn to another instrument is ONE cable.  No problem.  The horn is an
output only  device.  If you have both devices, getting the cable is cheap fun!

Eirikur