Voice Reserve Requirements ========================== The JV/XP synths can support a maximum of 64 TONES in simultaneous use. Such use is determined by several factors such as: simultaneous MIDI Note events whose "durations" are still ON; the status of the Tone Redamper Switch; and the controller ON switch status (values off=0, on=64) of CC64 (Hold1) Damper/Sustain Pedal. BTW, the Sound Canvas synth family requires a value of 102-127 for "variable" sustain qualities ON which is NOT per the MIDI Spec. Also, the Yamaha XG synths do "agree" with the JV/XP synth's usage (and the MIDI Spec) . In any case, using a song for an example using the following instrumentation and known maximum Part polyphony without considering CC64 or Redamper Switch status, produces the following info for Voice Reserve determinations: Patch Tones Polyphony Voice Reserve ===== ===== ========= ============= PR-B:001 Dist Gtr 1 3 1 3 PR-A:110 Steel Away 3 6 18 PR-B:013 Finger Bass 1 1 1 PR-A:054 Rocker Spin 3 6 18 PR-B:087 MG Lead 2 1 2 PR-B:001 PowerDrumSet 1 4 4 --- Total 46 Since 64-46=18, there are 18 "voices" (that is TONES) to spare for use in Voice Reserve. Though individual drum tones do have Redamper Switch settings, and their status can be determined from actual song usage, for simplicity's sake, I will not consider them due to not using a "defined" range of drum notes in my "generic" song example . Now let's determine the Tone Redamper Switch status in each Patch. Patch Tone1 Tone2 Tone3 Tone4 ===== ===== ===== ===== ===== PR-B:001 Dist Gtr 1 OFF OFF OFF n/a PR-A:110 Steel Away OFF n/a OFF OFF PR-B:013 Finger Bass OFF n/a n/a n/a PR-A:054 Rocker Spin ON ON ON n/a PR-B:087 MG Lead OFF OFF n/a n/a Since "Rocker Spin" is the only user of the Redamper Switch AND we have voice reserves to "spare", we'll "give" them to it, making the Part, to which the Patch is assigned, have a total of 18+18=36. In actual use, the Redamper Switch (or Damper affectiveness is determined by the use of CC64 and the System Status of the Hold-1 Receive MIDI Switch. Also, if the Damper (Hold-1) Control Switch is OFF the ReDamper Switch is ignored. BTW, in this case, the Damper Switch is also on for all of the tones of "Rocker Spin". Therefore the "practical" determining factor is the use of CC64, the Sustain/Damper/Hold1 controller for a Part's assigned Patch. Now to use the above Voice Reserve values in a song, use the following sysex, for a TEMP Performance, where the current song's parameters are stored. The address for the TEMP Performance Voice Reserve values for the 16 Parts, starts at 01 00 00 30. For reference, see page 151/144 of the respective Owner's Manuals for the JV-1080 or XP-50. In the below sysex message, the Part Patch assigments are assumed to be (but are easily adjusted) for a one-for-one Part/Channel correspondence for the six patches/instruments above Part/Channel, with the drums "required" to be on Part 10. Voice Reserve Values Needed Part 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Decimal 003 018 001 036 002 000 000 000 000 004 000 000 000 000 000 000 Hex 03 12 01 24 02 00 00 00 00 04 00 00 00 00 00 00 TEMP Performance Voice Reserve Sysex F0 41 10 6A 12 01 00 00 30 ... 03 12 01 24 02 00 00 00 00 04 00 00 00 00 00 00 0F F7 BTW, because the values should equal a maximum of 64, if you always ensure that they do so for this TEMP Performance Voice Reserve sysex, then the Checksum will always equal 0FH. Another reason for ensuring the use of 64, is to minimise any synth CPU processing otherwise required for voice "stealing".