5

The question is almost similar from this link. But the link there is already old, and the answer (to me) don't have enough detail :

MIDI CC 5 - Controls portamento rate to slide between 2 notes played subsequently.

MIDI CC 65 - Portamento On/Off switch | 0 to 63 = Off, 64 to 127 = On

MIDI CC 84 - Controls the amount of Portamento.

I use a very old Cakewalk Pro Audio 9 and USB midi cable connection from computer to Yamaha PSR-640. In the event list of track-1, I put something like this :

TEMPO : 100

MBT 1:01:000, CC-65, Value 127 (Portamento ON)
MBT 1:01:001, CC-5, Value 50
MBT 1:01:002, Patch Change, Value String Ensemble 1
MBT 2:01:000, Note C5, Duration 1:000
MBT 2:02:000, Note D5, Duration 1:000
MBT 2:03:000, Note E5, Duration 1:000

I can hear the glide from C5 to E5.

Somewhere in the internet (I'm sorry I cannot find the link again), I read that CC #84 controls the starting note to glide.

Since I don't know what is the starting note for each value (0 - 127) of CC-84, I just tried it by changing the value of CC-84 and CC-5

Here is the list with CC-84 :

TEMPO : 100

MBT 1:01:000, CC-65, Value 127 (Portamento ON)
MBT 1:01:001, CC-5, Value 50
MBT 1:01:002, CC-84, Value 100
MBT 1:01:003, Patch Change, Value String Ensemble 1
MBT 2:01:000, Note C5, Duration 4:000
MBT 3:01:000, Note D5, Duration 4:000
MBT 4:01:000, Note E5, Duration 3:000
MBT 5:01:000, Note F5, Duration 4:000
  1. Result : The C5 sounds muted, D5 to F5 sounds normal and I didn't hear the glide at all from C5 to F5

  2. From the same list, I only change the value of CC-5 from 50 to 100.
    Result : Now I can hear the glide from C5 to F5 (even there is a rest at bar 4:04:000) but the C5 still sounds muted while D5 to F5 sounds normal.

  3. From the same list, I've tried CC-5 = 127 and CC-84 = 127.
    Result : C5 still sounds muted (the rest of the notes sound normal) but now D5 sounds C5 and I didn't hear any glide. (Which I assume, D5 sounds C5 is actually the starting note to glide but not have enough time to glide because CC-5 = 127).

I hear the difference - but to be honest I can not make a conclusion so I still don't understand on how to implement it, in what kind of situation (for example) using these CC-65/CC-5/CC-84 and how is the event list look.

Any kind of help will be greatly appreciated. Thank you in advanced.

karma
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    afaik, the value of cc84 is the midi note number of your 'pre-porta' note, so maybe try something in audible range ;) then bend to somewhere musically close. C3 is 48, C4 60... The porta should [depending on hardware implementation] affect the next note actually triggered, so C5 in your example. [Though, to be safe, I'd set up your patch change well before any of that, in case it clears the buffers] – Tetsujin Mar 31 '18 at 19:38
  • @Tetsujin, thank you for your comment. But I'm sorry, I don't even know on how to do "try something in audible range ;) then bend to somewhere musically close". Do you mean put the value which is "audible range" in CC84 ? If the CC84 value is 48, then the starting note to glide is C3 ? Assuming I'm correct to get what you mean, I've tried that - still "nothing happen" :). – karma Apr 01 '18 at 15:01
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    This may be hardware-dependant. No-one ever properly agreed how porta ought to function; but if you send 65/127; 5/50; 84/48; Note C4.. you ought to hear a one-octave bend starting on C3, resolving to C4. It's too long ago for me to remember what generation the PSR640 belongs to, but it if was post 'XG' [circa 1995] then it ought to behave correctly. – Tetsujin Apr 01 '18 at 15:07
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    OK, I checked the gen, it's a 99, but I still don't remember its internal spec. If it is marked XG, it ought to behave 'properly'. If it's only marked 'GM' then it might not. – Tetsujin Apr 01 '18 at 15:12
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    @Tetsujin, PSR640 has XG also. I've tried your instruction, still no luck. I think I should give up :). BTW, I do a trick something like this : CC65=127, CC5=75, C3 duration value = 0 at MBT=1:02:119 and at MBT=1:03:000 C4 duration value = 1:000 (whole note). Of course I won't hear the C3, but when C4 on I can hear the gilde starts from C3 :). Thank you for your time, Tetsujin. – karma Apr 02 '18 at 18:44

1 Answers1

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The MIDI specification says:

When a Note-On is received after a Portamento Control message, the voice's pitch will glide from the key specified in the Portamento Control message to the new Note-On's pitch at the rate set by the portamento time controller.

CC84 should be a note number.

CL.
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  • thank you for the answer. But I still don't know how to implement it. "CC84 should be a note number" ---> yes, and it seems (if I'm not mistaken) Tetsujin say that a value 48 of CC84 is C3 note. Value 60 is C4 note. But still I don't know how to implement it :) – karma Apr 01 '18 at 15:05