Allocation Modes (Re: [sdiy] MIDI DCOs)

[Jeffrey D. McEachin]

At 07:01 PM 1/8/2004 EST, WeAreAs1 at aol.com wrote:

>I don't remember if the Prophet 2000 voices are rotated 
>sequentially (as in the Oberheim OBx/OBxa/OB8 and the Roland JP-8) or if they 
>are allocated by "note order stacking" (as in the Prophet 5).  

Uh oh, now you're talking about one of my favorite subjects.  ;)


>The sequential rotation (Oberheim type) is actually much easier to utilize, I 
>think - it also sounds better in many cases, since every new note comes from 
>the next voice.  It's more animated sounding, since each repeated depression 
>of the same note will sound slightly different, and in my opinion, it also 
>sounds better for sounds with long releases, unless you're trying to emulate a 
>piano or vibraphone!  

It starts out as sequential rotation, but if you listen closely, I think you'll find that the actual scheme is "assign in order of release".  For example, play 4 notes, and it will assign voices 1 2 3 & 4 in order.  If you then release the notes in reverse and play 4 more notes, the new notes should be assigned to voices 4 3 2 & 1 in that order.  At least that's how it works on many Roland synths.  This maximization of release time is why it sounds better for sounds with long releases.


>I think Sequential only used the other allocation method 
>(note order stacking) in the Prophet 5 in order to make the instrument feel like 
>it had more apparent polyphony while playing long release patches.

Note order stacking, as you call it, can be useful if you're using portamento or glissando and playing chords.  A slight roll of the fingers will make sure that each finger's note is assigned to the same voice from one chord to the next.  That way, the sliding notes don't cross each other.


The Roland Jupiter 6 has both allocation methods - sequential rotation is called poly1, and note order is called poly2.  And it has a solo, solo unison, and poly unison.  Add the Europa upgrade, and it has solo rotate (new note rotates to next available voice after turning off previous note, to preserve the release), and note stealing versions of all 3 poly modes (new note turns off the oldest currently playing note, releasing the new note restores the old note without an attack).

The MOTM-650 Midi-CV converter will have ALL of these allocation modes as well, plus selectable high, low, and last note priorities for the solo modes.  AFAIK that makes it the all time champion as far as voice allocation modes.


Hmmm...I just got a crazy idea.  How about a RANDOM voice allocation mode?  Seems like it could be useful with a modular - patch every voice differently, and your song would sound different every time you play it.  :)

JDM