Hi there and thanks for accepting me into this group.
As a quick introduction of myself, I'm from Germany, I have a number of 80s and 90s Yamaha synths, a nice bit of other equipment and some, albeit limited, knowledge in electronics (more of a software developer).
I recently bought a DX 7 Mk 1 - according to the chips' timestamp it's probably built in fall 1983. I have an issue with it where I am a bit stuck.
When I try to dump the internal memory, no MIDI interface recognizes any data, but something is being sent.
The setup I have for testing:
DX7 Mk 1 - MIDI out to a MOTU MIDI Express
No-Name USB-MIDI converter connected to the MOTU
Behringer FCA1616 connected to the MOTU
Process for dumping the memory (if I understood the manual correctly, there should not be an issue there):
Switch on DX7 ... :-)
FUNCTION - 8 (MIDI Channel 1) - 8 - YES (Sysinfo avail) - 8 - YES
Then I can see that the MOTU receives and relays something (the appropriate LEDs are all on for a time). I can see on both MIDI interfaces (no-name cable and FCA1616) that something is coming in, BUT no software on a PC (including DX Manager) sees any usable data.
It's the same if I plug the interfaces directly into the DX7 (the MOTU helps sometimes, my no-name cable for example has issues talking to a CS1x directly, but all is fine if the MOTU relays the data).
The DX7 can receive sysex, so I can send patches to it. Controller messages come out of the DX7. When dumping the sysex, the interfaces recognize the controller message for the "+1 YES", but after that nothing.
Another thing that makes me wonder if there is an issue with my DX7 is: when I switch it on, the MOTU registers a repeating signal coming in, but it is not relaying that (maybe the incoming is not strong enough?), but after having tried to dump sysex, this quick repeating signal is relayed (output LEDs start flickering).
And yet another potential hint: when the MOTU relays incoming signals back to the DX7, I actually see some data which looks very much like a sysex dump, but only the FCA1616 recognizes this f**ed up data stream, a small snippet of the data is:
F2 48 45
F2 41 56
F2 59 4D F2 45 54 F2 4C 32 F2 35 40
If you remove the "F2"s, you get the name of one of the stored voices "HEAVYMETAL25"
So, something somehow is coming.
Is it an issue you have seen? My only ideas are that either the sending rate is somehow wrong or the electrical level is not "strong enough", and the factual feedback when the MOTU sends all back to the DX7 barely raises the level above recognition? I mean, I'm purely guessing here, I also suspected the firmware, but according to the ability to dump a sysex is not known to be a problem of a firmware.
Any sensible idea, anything I could try, would be most welcome.
Maybe one more piece of potentially relevant info: when I pluck my TX7 into the same cables, all is well.
In the end this is for me more of a purist problem, as I would like to have my synthesizers all work to spec. I'm not planning on programming voices on the DX7 itself, I use software editors for that, and as I can send the patches over... Anyway, I don't like broken hardware :-)
Cheers, Florian
