Conference hydra::amiga_v1

    This is an interesting problem,and everybody wants to do it.
    Anyway, I am pretty sure there are pitch-follower midi translators.
    You would try to separate the 4 voices out into separate lines,
    one at a time or all at once into 4 MIDI voice followers.
    Then merge them with a midi merger and connect the MIDI output
    to a midi interface for your amiga, then use an amiga program
    that could take input into score form, such as deluxe music
    construction set for $70 or the other one for $400.  The other
    sequencing programs may not be n music notation, I'm not sure.
    DMCS then allows editing and printing and playing selected voices,
    and transposing.  However, without a laser printer, dot matrix
    scores may not be beautiful.
    Ask commusic notes about midi pitch controllers and mergers.
    Tom

    The hard part is turning an audio waveform into notes.  A friend
    of mine did this as a PhD thesis at Stanford in the 1970s, but he
    was limited to monophonic instruments, clearly not what you want.
    If you'd like a copy of his thesis, ask Stanford's CCRMA (advanced
    music department) for James A. Moorer's thesis.  At the time he
    did his work the music department was closely associated with the
    Artificial Intelligence project, where John Chowning invented FM
    synthesis.
    
    The hardware that Andy used was a 12-bit A/D converter attached
    to a PDP-6/PDP-10 multiprocessor.
    
    By the way, when Andy left Stanford he want to Industrial Light
    and Magic, the LucasFilm special effects group.  Last I heard he
    was working on their audio system, and complaining about the
    low data rate of MIDI.
    
    My conclusion: if Dr. James A. Moorer says it's hard, then it really
    is hard.  Your computer system is 15 years newer than his, but the
    usual audio A/D convertor for the Amiga is only 8 bits wide.  If
    you are serious about persuing this, use a 16-bit A/D and keep
    the entire waveform in memory during the analysis.  When you're
    done, I'd like to purchase your package.
        John Sauter

    It isn't hard if there is a product available for pitch-midi.
    I think there is, but it is probably monophonic.
    In the mid-70's there were no monolithic frequency-voltage convertors.
    It's easy to convert voltage to midi note numbers (adc to
    microprocessor to lookup table).
    Also, fast interval-counting technicques can be used.
    Your friend's 
    thesis is irrelevant to this problem, because this person doesn't
    have a DEC10 at home.  that thesis is probably swell for people designing
    new
    products, but it is probably the most expensive way to do it in
    a dedicated product, which is probably available for some hundreds
    of dollars.  It would be the cheapest solution (i.e., DSP)
    for a general-purpose product, such as a VAX.
    MIDI data rates are only slow for people locked into thinking in
    terms of digital audio.  Modern music probably needs a digital audio
    bus, too, but MIDI is a note-number protocol and sufficient for
    most pop music.  The problems that arise are not in the MIDI protocol
    but in actual implementations of synthesizers that react slowly
    and sequenciers that easily back up their output queues.

    Several significant developments in computer music were on DEC10s.
    Tom

Here is a note about pitch-midi on the usenet news.
Newsgroups: rec.music.synth
Path: decwrl!ucbvax!agate!ig!uwmcsd1!bbn!inmet!ishmael!inmet!authorplaceholder
Subject: Re: Pitch -> MIDI
Posted: 20 Sep 88 12:06:00 GMT
Organization: 
Nf-ID: #R:pyr.gatech.EDU:-641700:inmet:145600031:000:1209
Nf-From: inmet.UUCP!hedger    Sep 20 08:06:00 1988
 
 
There are several devices available to accomplish this task:
1) IVL Pitchrider mkII - I own one of these to midi my trumpet and
    it works quite well....it also has a real workhorse operating 
    system that lets you do things like send 6 note chords etc.
    price $699.00
 
2) I recently saw some promo material ( check out the last couple of
   issues of Electronic Musician, or Keyboard in the 'new development'
   type column) for a device specifically designed to convert voice
   to MIDI. Sorry I don't even know the name of the thing but it has its'
   own mike and a little sleek box with controls on it.
   price unknown.
    
3) Roland makes a device called (?) the VP70 which will convert mon source
   to MIDI. It also includes harmonization. 
   price around $1400.00.
     
4) Fairlight makes the Voicetracker which does what all of these boxes do
   but is supposed to do it best.
   price (not for us mortals) $3500.00.
    
  
 
****************************************************************
* Keith Hedger     ihnp4!inmet!hedger                          *
*    'flipper suffered for their music....now it's your turn'  *
****************************************************************