rlr@pyuxn.UUCP (Rich Rosen) (01/26/84)
A followup to Dave Burris' article on MIDI (Musical Instrument Digital Interface). (Interesting note: apparently this newsgroup's original charter involved discussion of computer applications in music. Dave's article was one of the first in a very long time regarding this topic.) An article in Musician magazine (#64, 2/84, p. 88) sheds some additional light on new MIDI developments. Roland has announced the MPU-401 interface, which finally provides a means of controlling MIDI-compatible instruments through a computer (currently using IBM-PC or Apple //e). Previously MIDI keyboards could control other MIDI keyboards, but that was about it. Roland (along with Sequential Circuits, Korg and others) produces a number of keyboards that are MIDI-controllable/compatible including a twelve-voice electronic piano, a series of "Jupiter" polyphonic synthesizers, as well as a digital drum box (TR-909) and (in the future) a MIDI guitar synthesizer. The way the MPU-401 works, you can program a part for any of four controlled MIDI instruments from any one of the four connected instruments intended for control. Thus, you can program the drum part by keying it in on the piano. (that's what the article says--it's not clear how this is done) I quote from the article: "The computer play[s] back the various [previously entered] parts on all four instruments simultaneously. Tempo can be varied to any speed, without change of pitch. Music can be transposed as desired. To be included in the software will be programs for varying degrees of timing error correction, provisions for editing phrases [!!!!!] and storage and playback of dynamics [!!!!!!!], involving not only the change of volume but of attack as well." The final paragraph of the article is interesting: "In a dramatic departure from industry practice, Roland has discarded proprietary privileges and has made the MPU-401 circuitry available to all interested software writers. It is their view that some of the great creative innovations to come in the MIDI field may well come out of garages, and it's hard to disagree." That means all music software hackers (if I can still legally use that word) will have a field day writing compositional software, song editing programs, etc. for this MIDI world. P.S. The MPU401 will retail for $175. I have a couple of questions about Dave Burris' earlier article. Does Moog really adhere to MIDI standards? On what machines? Moog has for the last few years been at the foreback of music technology, esp. in terms of compatibility with the rest of the world. Also, could Dave (or anyone who knows) please publish more info on MIDI standards and specs. It would be of interest to at least me, and probably many others. -- Pardon me for breathing... Rich Rosen pyuxn!rlr
rlr@pyuxn.UUCP (Rich Rosen) (01/26/84)
I should give credit where credit is due. That article in MUSICIAN magazine (2/84 issue) was called "Exponential Expose: Here Comes Midi" (A Sneak Preview of Digital's Next Quantum Leap) and was written by Bob Minshall. -- Pardon me for breathing... Rich Rosen pyuxn!rlr
burris@ihopa.UUCP (David Burris) (01/27/84)
I spoke to Bob Moog about a month ago at a seminar (by the way, he no longer owns Moog Music) and he said that Moog is currently adding a true MIDI interface to its new synths. and that a retrofit kit should be available for the Memory Moog in the near future. The Roland DG MPU-401 is the interface I've chosen to use with my combination of instrument and computer. I am already in the beginning stage of development for a software package in C language. I intend to develop composition, editing, record, playback tools. These may or may not be released to the public domain. I don't know how much detail on the MIDI I can give without violating the copyright by the International MIDI User's Group. I will give a brief description. For more information, contact: IMUG 8426 Vine Valley Dr. Sun Valley, CA 91352 (213)-768-7448 MIDI Hardware: The interface operates at 31.25 Kbaud (+/- 1%) asyncronuous start bit, 8 data bits, and stop bit 1.5 ma. current loop with receiver opto-isolated and turn-on current < 5 ma. & rise/fall times < 2 micsec. 5 pin DIN connector for interconnection. 50' maximum length The cable shall be sheilded twisted pair, with the sheild connected to pin 2 at both ends. Data Format: MIDI communication is acheived through multi-byte messages consisting of one status byte followed by one or two data bytes, except for real-time and exclusive messages. Message Types: I. Channel a. voice b. mode II. System a. common b. real-time c. exclusive Data Types: I. Status bytes a. running status b. unimplemented status c. undefined status II. Data Bytes Channel Modes: Omni - when on allows voice messages to be received in all voice channels without discrimination when off messages are received only in the selected channels Poly - when on any number of voices may be allocated by the receiver's normal voice assignment algorithm when off (Mono) the assignment of voice is one voice/voice channel Omni and Poly/Mono are independent for a total of four modes. Status Bytes Summary: Channel voice: note on/off key pressure/after-touch control change channel pressure/after-touch pitch wheel change Channel mode: local control on/off all notes off Omni mode on/off Mono/Poly mode System messages: system exclusive these messages are determined by the manufacturer of the particular device they should be publiched by the manufacturer system common song position counter song select tune request end-of-exclusive message system real-time timing clock start continue stop active sensing system reset -- Dave Burris ..!ihnp4!ihopa!burris AT&T Bell Labs, Naperville, Il.
malik@delphi.DEC (Karl Malik ZK01-1/F22 1-1440) (05/26/84)
SUBJ; MIDI People interested in MIDI should consider picking up a copy of 'this month's', June, KEYBOARD magazine. It has a lengthy discussion/interview with various MIDI gurus. - Karl
lou@qtlon.UUCP (06/07/84)
fnord
You may be interested in the British magazine "Electronics & Music Maker
(incorporating Computer Musician). The May 1984 (v4#3) issue is a MIDI
special with an Introduction to MIDI; Latest Spec;Complete Product Guide;
& Theory and Practice sections along with its usual articles AND a flexidisc
by AXXESS (aka the head of Lambourghini cars and records).
The single issue price is 95p.
Subscriptions from: Mail order dept.;E&MM;Alexander House;1 Milton Road,
Cambridge CB4 1UY
price: UK 15.50 pounds
Europe & overseas(surface) 16.20 pounds
Airmail overseas 37.50 pounds
You should be able to find issues in the States at most good magazine
stores.
cheers
lou's mythpeterh@azure.UUCP (Peter Hinsbeeck) (06/20/84)
I would like to make contact with anyone involved in software developmet for MIDI (Musical Instrument Digital Interface) controllers or applications. I have already contacted the International MIDI Association and am looking for additional contacts. Peter