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Conference napalm::commusic_v1

Title:* * Computer Music, MIDI, and Related Topics * *
Notice:Conference has been write-locked. Use new version.
Moderator:DYPSS1::SCHAFER
Created:Thu Feb 20 1986
Last Modified:Mon Aug 29 1994
Last Successful Update:Fri Jun 06 1997
Number of topics:2852
Total number of notes:33157

523.0. "121 Parts on 8 Tracks in 3 Generations " by ERLANG::FEHSKENS () Tue Sep 30 1986 12:59

    Some time ago I got curious as to just how many distinct parts you
    could record given some number of open tracks and a willingness
    to go to some number of generations on tape.  I toyed around with
    a few different strategies, decided the obvious one was the best,
    and after working a few examples explicitly decided there must be
    a (relatively) simple function that would compute this number.
    This function was derived empirically by observation, but a little
    thought convinced me that it made sense.
    
    The obvious strategy is to record parts on all open tracks but one,
    then mix down those parts to that last track.  Repeat this procedure
    on the remaining open tracks, and again, and again, etc., until
    all tracks but one contain mixdowns.  Mixdown all the mixed-down
    tracks to this remaining track.  Repeat as infinitum until you
    reach your generation limit. (Every time a part goes on tape,
    its generation number goes up by one.  "Live" parts are generation
    0.)  Note that each time you mixdown, you can add an additional
    part (whose generation number will be one less than "youngest" part
    in the mixdown).  This strategy has the property that it does not
    trash any parts until they have been successfully mixed down.  I.e.,
    if you don't like your first mixdown you can do it again.  This
    assumes that live parts are available for multiple takes if necessary.
    Once you've "committed" a mixdown by reusing its constituent tracks,
    though, you can't go back.
    
    The function is easier to describe if it's defined as the number
    of parts actually on tape, ready for mixdown.  Call this function
    
    	P(g,t)	(P for Parts)
    
    with
    
    	g = the highest generation number of the parts
    
    	t = the number of open tracks available to record on
    
    Then:
    
    	P(1,t) = t
    
    	P(g,1) = 1
    
    	P(g,t) = P(g,t-1) + P(g-1,t)
   
    Define
    
    	M(g,t)	(M for Mixdown)
    
    with g and t as above.  This is the number of parts available for
    mixdown, including the additional part added at mixdown time.
    
    Then:
    
    	M(g,t) = P(g,t) + 1
    
    	M(1,t) = t + 1
    
    	M(g,1) = 2
    
    	M(g,t) = M(g,t-1) + M(g-1,t) - 1
    
    
    
    The following table summarizes P(g,t) for useful values of g and
    t:
    
    
    				     g
    			---------------------------
    			 1	 2	 3	 4
    		t
    
    		1	  1	  1	  1	  1
    
    		2	  2	  3	  4	  5
    
    		3	  3	  6	 10	 15
    
    		4	  4	 10	 20	 35
    
    		5	  5	 15	 35	 70
    
    		6	  6	 21	 56	126
    
    		7	  7	 28	 84	210
    
    		8	  8	 36	120	330
T.RTitleUserPersonal
Name
DateLines
523.1BAXTA::BOTTOM_DAVIDTue Sep 30 1986 15:113
    Yeah but did you try it...and were the drums muddy?
                          
    dave stick in the mud
523.2Is This *Really* Necessary?ERLANG::FEHSKENSTue Sep 30 1986 15:3819
    I have two experiments scheduled (you know, "when I have some spare
    time..."):  the first is to simply record some representative stuff
    on track 1 of the 38, copy it to track 2, copy track 2 to track
    3, etc. until I've gone 8 generations, with and without dbx, and
    see how it goes; the second is to actually try to assemble something
    with 121 parts (it may only be 85 if I have to use a sync track,
    which I suspect I will; I suppose I could try *singing* 121 parts,
    with a lot of unisons to get a chorus effect), but the sheer amount
    of time involved (suppose it's a 30 second jingle; that's one hour
    of pure recording time, without considering rewind and setup times,
    or mixdown passes, even if I know *exactly* what I'm going to do)
    is intimidating to say the least.
    
    I'd expect my brain to be pretty muddy after an exercise like that.
    
    How about all my synthesizer voices playing a C major chord?
    
    len.
    
523.3Each voice individually panned, naturally....JAWS::COTEYou're too cool to fool...Tue Sep 30 1986 15:5210
    > I suppose I could try *singing* 121 parts,...
    
    
                    The Mormon Tabernacle Fehsken?
                    The Viena Fehsken Choir?
    
    
    Wanna sequence Beethovan's 5th? I have the score....
    
    Edd
523.4Megatracks?TASMAN::RHODESTue Sep 30 1986 15:5813
>    with a lot of unisons to get a chorus effect), but the sheer amount
>    of time involved (suppose it's a 30 second jingle; that's one hour
>    of pure recording time, without considering rewind and setup times,

You could probably make do with just a 10 second jingle.  Also you would
probably want each instrument to be distinguishable in the mix (all 121),
so that you could compare the sound quality after the final mixdown.

>    How about all my synthesizer voices playing a C major chord?
Using your formula one can see that you would need a 16-track for this ;^)

Todd.

523.5Next Idea I Have Gets Suppressed!ERLANG::FEHSKENSTue Sep 30 1986 17:0115
    re .3 - Edd - you obviously failed to notice the two foot-and-a-half
    thick stacks of scores over in the corner, which contain scores
    of all the Beethoven symphonies.  But that's understandable, as
    most of the floorspace in my apartment is buried under foot-and-a-half
    thick stacks of one thing or another.
    
    Regarding your title - sorry, but no, that's not possible.  The
    only panning possible using the strategy specified is to pan the
    last 8 mixdown subgroups individually; these 8 groups contain
    1, 3, 6, 10, 15, 21, 28 and 36 parts, respectively.  Now, you may
    ask, "where did these numbers come from?"  And you may say, "this
    is not my beautiful house"...
    
    len.
    
523.6Next Reply I Have Gets Suppressed!JAWS::COTEYou're too cool to fool...Tue Sep 30 1986 17:4214
    NO! NO! Suppress nothing!!!!!
    
    Some day I'll dig myself out of my 4 chanell foolishness and into
    the real world. Keep those ideas comin'!!!! They all get used 
    in some form, at some time.
    
    I hope you didn't take any offense at my comments. I just had this
    picture of 100+ little Len's all holding candles and dressed in
    white gowns and moustaches....
    
    Apology offered...
    
    Edd
    
523.7Can You Say "Overcommitted"?ERLANG::FEHSKENSTue Sep 30 1986 18:3215
    No, no, no offense taken.  I wanted to suppress my next idea because
    of the amount of work it's likely to generate for me.
    
    Your vision reminds me of my youthful days as a member of the choir...
    though I didn't have a moustache then.
    
    Speaking of work - do have any idea how much work it is to program
    46 drumming examples for 4 different drum machines?  All we're gonna
    have to do tomorrow night (assuming I actually finish the programming
    tonight) is push start and let the tape run for 17 minutes.  52
    patterns, 500 bars, about 600 MC500 editing operations!  The sequence
    even includes space for voice overs!
    
    len (who's losing control of his "projects").
    
523.8Supression was suppressed.....JAWS::COTEYou're too cool to fool...Tue Sep 30 1986 18:464
    Len - Somebody should give you an award (solid gold MIDI cord?)
    or something... You work too damn hard!!  Seriously....
    
    Edd