back to article Happy birthday MIDI 1.0: Getting pop stars wired for 30 years

Back in the early days of computer music, Reg man Bob Dormon was a professional recording engineer and music programmer. With a little help from some of his old music gear, he documents the rise of MIDI from a creative concept to its practical applications – which have ultimately led to its recognition as a Grammy Award-winning …


This topic is closed for new posts.
  1. PaulyV

    Still very little more satisfying than fumbling around behind your synth in the dark, MIDI cable in hand, and finding that it fits in first time, hence you had it the right way up. It's somewhat more niggling when you have to keep rotating it if you were not lucky enough first time. Happy birthday indeed.

    1. Anonymous Coward
      Anonymous Coward

      Having round plugs was probably the worst decision they made when coming up with MIDI, although to be fair, those plugs were commonly used for audio at the time, so it probably kept costs down.

      The only MIDI gear I use nowadays is a Novation SL connected to my PC, with a Nord Electro chained off it. Everything else is virtual now. It's a shame, as it's fun tweaking knobs and sliders on analogue synths, but they don't half take up space.

      1. Anonymous Coward
        Anonymous Coward

        They could have used much worse connectors. They at least go in and stay in, a 9 pin D plug would have meant using those screw in retainers to keep them in.

      2. JohnG

        "Having round plugs was probably the worst decision they made when coming up with MIDI..."

        Although choosing a whacky baud rate of 31200 that was not supported by commonly used UARTs of the day was also open to question.

        1. SysExJohn

          Baud rate.

          The rate of 31,250 was chosen as an exact subdivision of 1 MHz, the common frequency of an oscillator in those days. Just keep dividing by two.


    2. Anonymous Coward
      Anonymous Coward

      The only thing worse is the SCART socket, there's a real sense of achievement when you get one of those in first time. Only undoing a bra catch is more difficult than that :)

      1. Phil O'Sophical Silver badge

        Only undoing a bra catch is more difficult than that

        Practice makes perfect

        1. Anonymous Coward
          Anonymous Coward

          True, but asking ladies in the street for lessons doesn't seem to work :)

          1. Anonymous Coward
            Anonymous Coward

            True, but asking ladies in the street for lessons doesn't seem to work :)

            You need to ask the ones who aren't ladies...

          2. Phil O'Sophical Silver badge

            > True, but asking ladies in the street for lessons doesn't seem to work :)

            Not surprising, women never pay attention to TV connectors.

      2. Wam

        Don't get me started on SCART - maybe I was a cheapskate and got the crappy ones, but the shroud always used to come off, and the metal screen case fall apart - good riddance

        1. Mark 75

          Wasn't SCART a French invention?

          1. Phil O'Sophical Silver badge

            > Wasn't SCART a French invention?

            Yes: Syndicat des Constructeurs d'Appareils Radiorécepteurs et Téléviseurs, although the French call it a Peritel, not a SCART.

            Designed to allow easy connection of a Canal+ decoder with only one cable, used as a protectionist measure to prevent Japanese TVs being sold in France (no Peritel, no entry), and ultimately ending up on all TVs to get round the protectionist barriers. Probably the worst socket design, physically and electrically, ever developed.

      3. Naughtyhorse

        I'd hazard a guess that USB is more of a PITA that eight SCART or midi - it _always_ takes at least 3 goes to fit a plug with only two possible orientations!

  2. Mr C

    brings back memories

    Trying to connect my MIDI keyboard to my soundblaster on my 386 machine, trying to configure the Voyetra music software to get it to work.

    Had some good time there, did not serious or constructive but it represents a nice era when you had to figure stuff out by yourself, no Google back then.

  3. Anonymous Coward
    Anonymous Coward

    That first illustration ...

    ... wouldn't look out of place on the cover of a Devo album, which is rather appropriate 'cos Jim Mothersbaugh (brother of Mark, of Devo fame) was one of the folks at Roland who worked on the MIDI spec during the 80s. Whilst 'proper' analogue synths have their adherents, I'll take MIDI over faffing around in the dark with patch cables, thankyouverymuch.

    Nice article - brings back fond memories of writing a MIDI sequencer in 68000 assembler for my Atari ST because I couldn't afford Cubase.

  4. David Given

    One really cool feature... that MIDI cables don't actually make electrical connection --- each cable just completes a loop between the sending device and the LED of an optoisolator at the receiving end. Ground is supplied by the sending end and isn't connected to the receiving end at all. (Some of the cables I've seen didn't bother with a ground and used plastic DIN plugs; they feel really weird.) This means that in the notoriously ghastly electrical environment of a stage, you don't run the risk of plugging together two expensive bits of kit and watching them asplode due to hideous ground loops just before the gig.

    You can find the circuits here:

    A side effect of this is that they're *current* switched, not *voltage* switched. Logic 0 is specified by pushing 5mA through the circuit (in the right direction). The voltage is pretty much irrelevant; I'm sure there are limits, but the specs I've found don't specify one. (Although most people seem to use 5V.)

    1. Anonymous Coward
      Anonymous Coward

      Re: One really cool feature...

      I think that was more of an necessity than a selling point :)

      It avoids ground loops and other things.

    2. Iain 15

      Re: One really cool feature...

      And then along came USB midi and undid all that good work. Now I am stuck with isolators in every port just to keep the buzz down.

      1. handle

        Re: One really cool feature...

        The very comprehensive article does mention opto-isolation. I wish DMX lighting control did the same thing. With DMX you often have lamps on different mains phases where earth potentials can be a long way apart, and with all that mains flying around, the potential for it getting into the DMX chain and frying a whole string of lamps and the lighting console is significant. Perhaps fast enough opto-isolators weren't cheap at the time, or the lighting guys weren't as acutely aware of earth loops (being more likely to be the perpetrators of interference than the victims of it!)?

        Incidentally, every ethernet port contains galvanic isolation, but by transformer rather than opto-isolator.

        Regarding baud rate, I thought it was so that cheap NTSC subcarrier crystals could be used to generate the clock, but the figure doesn't make sense. DMX is also a non-standard rate of 250kBaud, but that's because it's easily obtainable from microprocessor clocks of 1MHz * 2^n.

        1. Anonymous Coward
          Anonymous Coward

          Re: One really cool feature...

          Re: DMX: I've never experienced or even anecdotally heard of a desk, light or dimmer being damaged in any way in the manner which you describe. I worked for about ten years in lighting, in medium venues (Brixton Academy sized) and at festivals. Festivals had multiple generators and consequently different frequencies as well as phases all over the place.

          The reason that DMX has the baud rate it has is because it left enough processing power to run a desk on the 8bit processors of the day, after dealing with the PIO.

          1. handle

            Re: One really cool feature...

            OK, maybe I'm just being paranoid about the prospect of damage, although I have read recommendations to put the interface chips in sockets so that they are easy to replace.

            However, I have definitely experienced problems due to using lights on different phases in the one DMX chain, which opto-isolators ought to solve. (I say "ought to" because I didn't have such a thing to test the hypothesis at the time.)

            Mystery about MIDI's odd baud rate not solved yet. :)

            1. Quxy

              MIDI's odd baud rate

              31,250Hz was chosen because it was a unit fraction of the 4MHz clock used in the cheap 8-bit MCUs of the early 80s. I designed several commercial instruments with MIDI interfaces, and recall that we didn't use a separate UART chip (which required odd, higher-frequency crystals), but simply divided by 128.

            2. SysExJohn

              Re: One really cool feature...

              1,000,000 /2







        2. Richard 12 Silver badge

          Re: One really cool feature...

          The ANSI E1.11 - DMX512A standard requires the receiving circuit to be electrically isolated, and has done since 1990. IIRC, only the original 1986 version of the standard didn't require it, but did recommend it.

          See sections 4.6, 5.7 and Figure 3. (There may be an RF bypass capacitor to Chassis, but nothing else.)

          There is some very old (pre-1990) reputable kit without it, but nothing reputable designed since 1990.

          Unfortunately, there are a lot of cheapskate pieces of **** which use an explicitly disallowed receiver circuit which breaks that isolation, either to save ~5p on 5V-ISO and opto or because they have never actually read any of the standard. I'm guessing the latter, as there's been a lot of inaccurate or outright wrong info on the Internet over the years. (Including some app notes with firmware (PIC) that get it wrong.)

          This kind of equipment can usually be identified by the 3-pin XLR connector labelled "DMX", which is also specifically prohibited by the standard.

          The standard is currently available for free from PLASA Technical Standards Program.

          The reason MIDI uses current loop and DMX512A doesn't is that MIDI is a point-to-point (daisychaining is not recommended, but works for very short runs), while DMX512A is 31-receiver multidrop over very long (500m) runs where the devices could be a long distance from each other.

          Current loop doesn't work for a long multidrop run as the resistance of the cable means the current vanishes into the first couple of receivers.

          1. Tridac

            Re: One really cool feature...

            Current loop ?.

            I worked in sound engineering / mixer design in London in the 1970's (shows my age, etc :-) and then went on to work on an electronic piano micro controller design for HH Electronic in 1979. It was an 8 note polyphonic design that used a 6502 cpu and various cmos logic to provide a touch sensitive keyboard. It also had a serial current loop interface running at 31.25Khz, that allowed coupling between two or more pianos, sequencer or other instruments, so that playing any instrument in the loop would play the others as well. The interface used a 25 pin D connector, frame oriented protocol with checksum and, iirc, optocouplers at the receiving end. Software development using a Rockwell AIM65, with the sort of single line assembler where you have to go back later to fill in all the branch targets.

            Mike Harrison, the MD of HH, had plans for a whole range of instruments, but the company went into receivership later. Anyway, uk design and many, many years before midi hit the market and very similar in concept...


        3. Naughtyhorse

          Re: One really cool feature...

          errrr if thats even a remote possibility why not use star connected 3 phase supplies?

        4. SysExJohn

          Re: One really cool feature...

          Just divide by two a few more times and 31,250 is the answer.

  5. hammarbtyp

    The irony...

    I do like the irony of the 1st picture of the kids in a birthday party surrounded by all those electronic gubbins, waiting patiently for Mummy to start her rendition of "Happy birthday to you" and not realizing that as soon as she is past the first line, the windows will be blown in by a crack squad of DMCA lawyers, who will drag her away for playing copyrighted music without first paying the appropiate licence fee

    1. Anonymous Coward
      Anonymous Coward

      Re: The irony...

      Yep it will be Guantanamo Bay for her with no possibility of release and this heinous crime was detected all thanks to the guys at the NSA and their PRISM program.

    2. Tom 7 Silver badge

      Re: The irony...

      The music for Happy Birthday is out of copyright (was 'good morning to you') and you can sing something in polish or something that's phonetically is identical to Happy Birthday but released under a creative commons so just say yo mama was singing that.

      1. Anonymous Coward
        Anonymous Coward

        Re: The irony... @ Tom 7

        They shoot first and ask questions later

  6. Anonymous Coward
    Anonymous Coward

    An thanks to MIDI.... why the Atari ST, with it's built in MIDI ports, was king in the Studio / Home studio and not the PC or Amiga. Never once did I have connectivty issues with the ST and later my Facon 040 (yes a mod'ed 030). When it came to music software it was rock solid, unlike the PC when the soundblaster would just randomly just spew out utter crap.

    1. Anonymous Coward
      Anonymous Coward

      Re: An thanks to MIDI....

      The brain ache that's involved with PC based sequencers is why I went back to using an old Roland MC-50 hardware sequencer. Dreaded the floppy drive failing, but then found the HxC emulator that allows you to use an SD card instead. Now I'm just dreading the LCD or alpha dial failing ...

    2. PaulyV

      Re: An thanks to MIDI....

      No doubt at all that I was most creative using a system based around my Atari. Admittedly much of it had to do with my age at the time and hence my ability to spend days on end on such matters.

      Having the computer there to do one task alone, namely sequencing, resulted in a very focused approach, which is as it should be. I could not afford a 1040 ST, nor the 'hi-res' monitor, let alone Cubase (I still recall when it was called Cubit), so it was a 520 ST, a black and white TV and a purchase of Midistudio Master by some outfit called Ladbroke Computing for me. A great program that never crashed or trashed...even on stage in many a humid pub. I seem to recall the setup being a Juno 106, D50, Casio CZ3000 and a Boss DR550 drum machine. 4 instruments but so many possibilities. The only issue with my Atari was the extended screen draw times when you were working on longer tracks. Served me right for writing tracks of indulgent length - blame The Orb.

      Sorry - got caught up reminiscing there!

    3. Elmer Phud

      Re: An thanks to MIDI....

      Ah, memories of a CZ101 and a Speccy and a homemade lead and library instructions printed out in silvery paper.

      Or two Speccys, two MIDI interfaces and a drum machine and a sampler - fine until playback ended and sometimes both machines crashed.

      Kids these days blah blah blah

    4. John Smith 19 Gold badge

      Re: An thanks to MIDI....

      " why the Atari ST, with it's built in MIDI ports, was king in the Studio / Home studio and not the PC or Amiga. Never once did I have connectivty issues with the ST and later my Facon 040 (yes a mod'ed 030). When it came to music software it was rock solid, unlike the PC when the soundblaster would just randomly just spew out utter crap."

      Although some on stage even used the Psion II (saw it in an edition of PCW).

  7. stucs201

    unique applications that have nothing to do with music

    That'll be midi maze on the ST then.

    We even have an icon for it --->

    1. Cihatari

      Re: unique applications that have nothing to do with music

      And not just Midi Maze either.

      A more contemporary FPS called 'Substation' came along in the twilight of the commercial life of the Atari ST family. This allowed for multiple players via MIDI link too. This one was for the enhanced 'STE' and Falcon. It was notable for Goraud shading instead of texture maps for the walls, a wickedly directional in-game stereo audio system and was more than capable of ratcheting up tension in the bug-hunting phases.

  8. TheOtherHobbes


    "You could, of course, play actual drum machine rhythm patterns into synths, but you’d soon wish you hadn’t as you’d discover them to be repetitive and most likely atonal with dubious musical merits."

    Not always. I was in an 80s band (hair to match) and our drum machine did double duty as a sequencer.

    The secret was to make the drum machine spit out MIDI notes in the key of the song.

    Get it right and you had a supremely tight insta-backing, and a good source of ideas too.

    MIDI, however, continues to be a bit pants. While it certainly did the revolution thing (good) it was never quite fast enough for complex sequencing with a lot of modulation (bad).

    It didn't help that the handful-of-MHz 8-bit micros in most synths added random-ish delays of up to 10ms while they worked out which note to play, then set up the hardware to play it.

    OSC today is much more flexible. It's far faster, and you're not limited to numbered notes - you can send absolute frequencies in Hz for fretless instruments.

  9. TheWeenie

    Takes me back!

    I wrote a very basic network stack once, using two Atari STs connected via their MIDI ports. You'd press a key on one ST, and the output would appear on the screen of the other. This was in 1994 using STOS.

    I'm sure it goes without saying that I got a LOT of women back then. Unfortunately just not in real life.

  10. Phil Atkin

    30th anniversary of MIDI, 50th anniversary of the Mellotron!

    A good year for unguitars and undrums I'd say.

  11. John Smith 19 Gold badge

    For a good look at the electronics of the era try

    "Musical Applications of Microprocessors by Hal Chamberlain."

    It has all kinds of stuff in it from voltage control (Common state of practice at that time), the new fangled MIDI right into DSP and Fourier Analysis and synthesis in assembler (probably not for the feint hearted).

  12. Anonymous Coward
    Anonymous Coward

    Midi Today

    I recently bought a Peavey Vypyr Amp. Remarkably the only to update it's firmware is via midi. The thing has a USB port but the makers decided that Midi was the way to go. You can waste many days trying to send control messages to it, which it ignores. I cannot fathom what arsehole made that decision. Had I know about the midi only update, I'd never have bought the amp. Buyer beware.

  13. DaneB

    Well researched article all-round. Happy 3decades MIDI !

  14. Will Godfrey Silver badge

    And many more birthdays I suspect.

    Still a happy MIDI user connecting various hardware synths to my DAW. Never had any significant problems with it unlike most 'modern' comms. The only thing I've ever found simpler and more bullet-proof is RS232.

  15. Anonymous Coward
    Anonymous Coward

    Have aliens taken over El Reg?

    Good lord...five pages of in-depth technical flim-flammery (I mean that in its most complimentary fashion)? It was like reading an old issue of Byte magazine. Remember those 'some assembly required' columns? You ended up building a disk controller out of a tin can and still haveing to program it yourself. In Z80 assembler.

    Anyway, to get back on topic, my muso friend claims that whilst MIDI was jolly useful, it wasn't until they stuck a controller on the Atari ST that it really took off. From that moment any spotty yoof could sound like they knew what they were doing. Comments?

  16. Kenwana

    Let's do the midi dance!

    It's a shame they met their Chan 1 Note off on a mountain road though.

  17. Anonymous Coward
    Anonymous Coward

    just happy to see that there's a reference to my TR 606 in one of the pics

  18. Down not across
    Thumb Up

    Wow. A nice in-depth article. Such articles used to be the standard on El Reg. Once upon time.

    Anyway I'm sure I saw MPU-401 and CM32 in the cupboard somewhere the other day. Have to go dig them out now and see if any of the old boxen with ISA slot still work..

  19. LinkOfHyrule

    Great article!

This topic is closed for new posts.