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SEQUENTIAL/DSI => OB-6 => Topic started by: wreckington on March 24, 2022, 08:24:04 PM

Title: Issue with OB6 polychain
Post by: wreckington on March 24, 2022, 08:24:04 PM
I've had an OB6 module for quite a while and picked up a keyboard version to polychain with it but I've got a weird issue.

On some patches the voices do not all trigger.  If I press the keys, it will play 6 times and then blank 6 times in that order.  This happens with factory patches as well as other patches I have made or imported.

If I have the keyboard set to poly, the notes do not fire even if I do not have the module turned on.  If I turn off poly mode it will play the patch normally on either or both together.

I opened a ticket.  Ive tried a bunch of things with the settings but nothing seems to have any effect on this behavior. I am concerned something might be wrong with the keyboard.

Anyone seen anything like this before?  It affects maybe 1 in 10 patches
Title: Re: Issue with OB6 polychain
Post by: LPF83 on March 25, 2022, 05:21:11 AM
I've had an OB6 module for quite a while and picked up a keyboard version to polychain with it but I've got a weird issue.

On some patches the voices do not all trigger.  If I press the keys, it will play 6 times and then blank 6 times in that order.  This happens with factory patches as well as other patches I have made or imported.

If I have the keyboard set to poly, the notes do not fire even if I do not have the module turned on.  If I turn off poly mode it will play the patch normally on either or both together.

I opened a ticket.  Ive tried a bunch of things with the settings but nothing seems to have any effect on this behavior. I am concerned something might be wrong with the keyboard.

Anyone seen anything like this before?  It affects maybe 1 in 10 patches

I've never polychained mine, but wondering if the affected patches are unison mode patches by any chance?  If you can identify a common element in the patches that are affected it might fast track your answer.
Title: Re: Issue with OB6 polychain
Post by: kpatz on March 25, 2022, 02:53:54 PM
I haven't tried polychaining mine either, but then I only have a single OB-6 module.

6 notes playing and then 6 not means those second 6 notes are being sent to the slave and it's not receiving/playing them.

From RTMing, it seems that you only need to set polychain on the master, not the slave.  Also, I would assume both synths need to be on the same MIDI channel.  Lastly, on the master, is MIDI Out set to the correct port (MIDI or USB), as well as MIDI Sysex?  How are the two synths connected?  Assuming DIN MIDI from master to slave, you'd want to set both MIDI Out and MIDI SysEx to MIDI.  Also, check Param Xmit and Param Rcv to make sure they match up on both synths.

I don't know if the master sends patch data to the slave when polychained, or if you have to do a patch dump to match them up.  If the slave is in unison and the master in poly on the same patch, that could cause an issue as well.

I'm assuming you're using the OB-6 Keyboard as the master and the module as the slave?  With Polychain turned off, do both synths play when you play the keyboard?
Title: Re: Issue with OB6 polychain
Post by: agavephoto on March 25, 2022, 03:39:31 PM
This is a known bug in polychain mode, and the solution is to turn off chord unison mode (this affects any patch saved with chord unison mode, even if the default for that patch is unison OFF). So, just set the unison mode off of chord mode, and then notes 7-12 should be sent. I found this with FW 1.6.6, and Sequential confirmed it via support email despite it not being on the known issues page. I have not yet tried FW 1.7.4. 

[Edit: formatting consistency]
Title: Re: Issue with OB6 polychain
Post by: wreckington on March 25, 2022, 09:06:37 PM
This is a known bug in polychain mode, and the solution is to turn off chord unison mode (this affects any patch saved with chord unison mode, even if the default for that patch is unison OFF). So, just set the unison mode off of chord mode, and then notes 7-12 should be sent. I found this with FW 1.6.6, and Sequential confirmed it via support email despite it not being on the known issues page. I have not yet tried FW 1.7.4. 

[Edit: formatting consistency]

Wow thank you so much.  I've been wracking my brain over this and that fixed it!

Still an issue with 1.7.4.  I went in an changed the patches on my keyboard only and the issue is totally resolved.