"Anyone know what the U2 component can be replaced with? I've got one that's blown, wondering if it could be fixed with some equivalent part." - wingerr
I've got a D/A box with "4558D JRC" printed on the IC in that location. Which doesn't make a lot of sense because that's a 741 (ugh) replacement, and isn't exactly designed for low voltage operation.
"In fact, there was a reason, it seems that early MIDI standard only had "All Note Off" 0x7B. So we should end sending both to keep addressing early 80's synths ! Usual "Panic buttons" often send both as well probably for this reason." - Mr_Dham
Interesting! What is the source of this information?
If you send both 0x78 and 0x7B, which do you send first (or does it matter)? I assume the real note-off (note-on with vel=0) is sent before either?
I have a French book written in 1990 about MIDI standard, it descibes only 0x7B.
I aslo have a PSR 500 (1990) that only has 0x7B in its MIDI implementation chart as well.
I just browse MIDI implementation chart of Roland D50, Korg M1, and it's the same, 0x7B only...
My Roland VK7 (1997) has both 0x78 and 0x7B.
0x7B stops the note (but sound can remain due to long release, sustain pedal, ...)
0x78 stops the sound (what ever is release length or sustain pedal state).
It is a bit overkill, but if I had to send both, I would send 0x7B before 0x7A78 (edit -> corrected the typo error)
Note-off was normaly sent before pushing MUTE. Except if the player didn't approach left hand before (hence the utility of 0x78 / 0x7B messages )
"I have a French book written in 1990 about MIDI standard, it descibes only 0x7B. I aslo have a PSR 500 (1990) that only has 0x7B in its MIDI implementation chart as well. I just browse MIDI implementation chart of Roland D50, Korg M1, and it's the same, 0x7B only... My Roland VK7 (1997) has both 0x78 and 0x7B." - Mr_Dham
Ah, thanks!
I'm looking at a Yamaha SHS-300 manual and it responds to both, but only transmits 0x78.
The StudioLogic Numa Compact 2 only transmits 0x7B.
I guess it's safest to transmit both. MIDI sure is a vague "standard".
I guess it's safest to transmit both.
MIDI sure is a vague "standard".
Yes, we have here a typical example. We almost can imagine fruitless discussion that lead to the creation 0x78 message in the late 1990's...
"It is a bit overkill, but if I had to send both, I would send 0x7B before 0x7A78 (edit -> corrected the typo error) " - Mr_Dham
I believe one could use running status here too to shave off a byte: 0xB0|ch, 0x7B, 0x00, 0x78, 0x00
But maybe that's asking for trouble?
Running status is part of the early standard (it is described in my 1990's book), so it should be safe, but...
When you are sending "All Note/Sound Off" you are also stoping generating MIDI traffic.
Then I see no express reason for trying to shave off a byte with running status.
So, if you want to be very safe, take all your time and send:
0xB0|ch, 0x7B, 0x00,
0xB0|ch, 0x78, 0x00,
"Anyone know what the U2 component can be replaced with? I've got one that's blown, wondering if it could be fixed with some equivalent part." - wingerrI've got a D/A box with "4558D JRC" printed on the IC in that location. Which doesn't make a lot of sense because that's a 741 (ugh) replacement, and isn't exactly designed for low voltage operation.
"Then I see no express reason for trying to shave off a byte with running status." - Mr_Dham
Thanks! You're absolutely right, what's one byte in the larger scheme of things? "For want of a byte the kingdom was lost..."
"I may just try it and see if it works." - wingerr
Good luck!
"Then I see no express reason for trying to shave off a byte with running status." - Mr_DhamThanks! You're absolutely right, what's one byte in the larger scheme of things? "For want of a byte the kingdom was lost...""I may just try it and see if it works." - wingerrGood luck!
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