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Prophet 08: Doesn't work MIDI In when connecting the outputs

Prophet 08: Doesn't work MIDI In when connecting the outputs
« on: September 08, 2018, 06:22:16 AM »
My Prophet 08 rack doesn't work MIDI In when it's connecting to any Mixer or Sound Card.
Having tried to test for many times that I figured it out when my 08 is connecting to my O1V or FireFace 400, it's not working at all.

Is it something issues on my O1V and Fireface 400 affecting my 08 not to trigger MIDI inputs?
Anyone can help?

M

Re: Prophet 08: Doesn't work MIDI In when connecting the outputs
« Reply #1 on: September 10, 2018, 03:01:50 AM »
Moinmoin Murray,

be a little more specific:
- What exactly are You doing?
- Does Your module really work with an external amplifier or headphones and only stops working when connected to a soundcard?
- What MIDI connection / configuration do You use?
- Did You RTFM (sorry: consult the P08 user manual, that is) regarding P08 global settings?

In my experience the P08 MIDI implementation is quite good and complies to the documentation.

Live and at rehearsals I use P08 MIDI out to control a 19" sound module and sync everything to foot-taps by connecting an external MIDI clock pedal to P08 MIDI in, setting the clock (P08 global settings) to MIDI In/Out, and transfering the clock signal via P08 MIDI thru to external effects.

At home I have been using an old KAWAI-sequencer for a long time, sending and receiving direct MIDI commands (key, CC, NRPN, ... ) but just lately switched to Ableton using direct MIDI commands as well as PlugSE, a VST-PlugIn controlling P08.

All these MIDI-applications work as documented. So if You set up everything correctly and the error persists, You should ask DSI/sequential support. As I understand, they are now reachable at https://www.sequential.com/support/contact-support/

HTH

Martin

Re: Prophet 08: Doesn't work MIDI In when connecting the outputs
« Reply #2 on: September 10, 2018, 06:27:07 AM »
Hello Martin

> - Does Your module really work with an external amplifier or headphones and only stops working when connected to a soundcard?
Yes, my 08 is fully working to play audio from its outputs (Main and B).
As far as my investigation, when my 08 is connecting to my old O1V via phone plug, it won't work.
It seems my O1V making the issue rather than my 08.
Do you think the issue would be happened?

> - What MIDI connection / configuration do You use?
MacBook Pro -> Fireface 400 (MIDI output) -> P08 (MIDI input)

- Did You RTFM (sorry: consult the P08 user manual, that is) regarding P08 global settings?
Yes, a lot. Tried to test it with different parameters (like NRPN, CC etc) in order to sort it out.
But it doesn't have any luck.

> but just lately switched to Ableton using direct MIDI commands as well as PlugSE, a VST-PlugIn controlling P08.
Mine is the same setting as you!
But it doesn't work.

It might need my P08 repaired which would be shame.

Re: Prophet 08: Doesn't work MIDI In when connecting the outputs
« Reply #3 on: September 11, 2018, 01:55:55 AM »
Hmmmm...

what we can try to do is a systematic approach to locate the error:

The first thing to look at is the P08 module's LEDs (labeled 1 to 8, just below the master volume). Do they react on MIDI in signals from Your MacBook?
  • If they do (flash according to MIDI key messages), the MIDI connection is at least established, the error will likely be at the AF side -> check P08 line outputs, AF-cabling, mixer/soundcard.
  • If they don't (stay dark), there is a problem at the MIDI side of things -> check MIDI software, hardware, configuration and connection.
Not in theory but in real life there could be a third possible reason (massive ground problems), but we will come to that later, let's stay to our systematic approach.
Do the test described above
  • with P08 connected to Your mixer and soundcard
  • connected to nothing but MIDI in (maybe controlled by headphones connected to P08 headphone out).
Any difference in the behaviour of the LEDs?

The next test is only useful, if Your P08 outputs the correct AF-signal via headphones with an active MIDI-connection MacBook -> Fireface -> P08:
  • What happens, if You connect Your MIDI-controlled P08 via its headphone output to mixer/soundcard input using a standard stereo TRS - TRS cable (P08 LEDs, AF-signal at the mixer's in)?

Martin


« Last Edit: September 11, 2018, 02:02:17 AM by MartinM »

Re: Prophet 08: Doesn't work MIDI In when connecting the outputs
« Reply #4 on: September 11, 2018, 03:39:28 PM »
Hello Martin

> The first thing to look at is the P08 module's LEDs (labeled 1 to 8, just below the master volume). Do they react on MIDI in signals from Your MacBook?
MacBook Pro -> FireFace 400 (MIDI out) -> P08 (In) doesn't flash the Red LEDs.
   
> If they don't (stay dark), there is a problem at the MIDI side of things -> check MIDI software, hardware, configuration and connection.
It all works for my MachineDrum and Zarenbourg.
It means the only problem is on P08 which is really weird.

> Not in theory but in real life there could be a third possible reason (massive ground problems), but we will come to that later, let's stay to our systematic approach.
It seems to be correct as you guess.
When my P08 doesn't connect to my O1V, it can flash the LEDs by MacBook Pro to play some audio.
When connecting to it, it won't flash (no audio at all).

> The next test is only useful, if Your P08 outputs the correct AF-signal via headphones with an active MIDI-connection MacBook -> Fireface -> P08:
The below settings totally work my P08 via the routing without the O1V. I don't know why,,,,,,
- Zarenbourg (MIDI out) -> P08 (MIDI out)
- MacBook Pro -> FireFace 400 (MIDI out) -> MachineDrum (MIDI in) - MIDI Thru -> P08 (MIDI in)

It's so weird i don't know what to do.
 
My Fireface 400 and O1V are so old gears which might be partially broken????

M

Re: Prophet 08: Doesn't work MIDI In when connecting the outputs
« Reply #5 on: September 12, 2018, 11:00:29 AM »
> The first thing to look at is the P08 module's LEDs (labeled 1 to 8, just below the master volume). Do they react on MIDI in signals from Your MacBook?
MacBook Pro -> FireFace 400 (MIDI out) -> P08 (In) doesn't flash the Red LEDs.
and
Quote
It seems to be correct as you guess.
When my P08 doesn't connect to my O1V, it can flash the LEDs by MacBook Pro to play some audio.
When connecting to it, it won't flash (no audio at all).

So this is the actual state:
  • P08's LEDs show the assignment of MIDI = keyboard presses, whether by keyboard or MIDI in to the P08's VCOs = voices.
  • Your tests show flashing LEDs if line-output is not connected to the mixer, but LEDs staying dark  in exactly the same configuration when connected to the mixer.
This indicates a lack of MIDI in control if and when the mixer is connected, as the VCOs are not even assigned to MIDI in signals.
I can imagine two reasons for that:
  • massive ground problems spoiling all MIDI in signals when MIDI and mixer are connected
  • mechanical problems breaking MIDI in connection (what however only should occur if tension is applied to the cabling when it is connected)
As a last test You should use a MIDI cable, that only connects pins 4 and 5 of the 5-pole DIN plug. A "normal" 5-pole DIN cable will connect the other pins and the sleeve = ground also and thus may result in a ground loop introducing ground problems.
I do not know for sure but cannot imagine the P08 does not comply to the MIDI hardware standard, demanding opto-(de)coupling for pins 4 and 5 in order to avoid ground loops. So If only 4 and 5 are connected between the partners on both sides (Fireface and P08), a ground loop will be excluded as a reason for the behaviour described by You.

If this doesn't cure Your problem, ask DSI/sequential support.

HTH

Martin

Re: Prophet 08: Doesn't work MIDI In when connecting the outputs
« Reply #6 on: September 14, 2018, 01:39:40 PM »
Hello Martin

Thank you very much for your all support.
I will try to test it according to your advices.

M