Possible to control fader going out of L/R with midi pedal?

[Mbirame]

Hi,
My question is a bit complex so bare with me. I have a QU-16. We use scenes for each song so I can’t use a solution that requires switching scenes…

I am hoping to control the vocals for my wireless headset mic with a Behringer midi foot controller pedal. I want to be able to turn down the fader on channel 7 for the L/R only, but not change the monitor levels. Is this possible?

To further complicate things: Occasionally (when we have a dedicated FOH person), I need to be sending the vox out of Mix 4 instead of L/R, so I would like to be able to easily swap which channel is being controlled by the foot controller.

I have been diving in to the Midi proticol manual, and honestly it is really confusing to me-the whole MRPN stuff makes me go crosseyed.

So to start: is it possible to control the fader for one channel going into the L/R without affecting the level going into the mixes? Thanks-and happy holidays!

[Anonymous]

Assuming the monitors are preface, as they normally would be.

Then just control the fader, or the mix level, should be (relatively) simple

[Mbirame]

Awesome! Any idea on how to achieve this (relatively)simple task? Because this makes no sense to me:

Attachments:

You must be logged in to view attached files.

[Mbirame]

I am using a Max For Live plugin in Ableton right now to send NPRN out just to try and create the message I am needing to test before I deal with the foot pedal. I am having a hard time reconciling what the QU-16 manual is saying vs what NPRN signals seem to be coming out. For example, the manual says I am sending something in this format:

BN, 63, CH, BN, 62, 17, BN, 06, VA BN, 26, 07
Where VA –inf to +10dB = 00 to 7F, 0dB = 6B

I do not understand where the 63, 62, 06, and 26 above come from, as my limited understanding of NPRN, is that the center number for the NPRN message would be 99, 98, 06 (matches), and 38. Indeed, that is what the M4L patch sends out as well.

I also have no idea what “BN” is referring to above and I don’t see it anywhere in the manual.

What I am sending out of the M4L patch is this message:

176 99 1 (signifying channel one?)
176 98 17 (signifying the fader of that channel? The”ID” that the manual talks about)
176 6 0 (course control change, so this is the Data MSB I think? I have this at “0” for all the way down).
176 38 0 (Data LSB again at 0 so that it puts the MSB all the way down)

Then for full fader up (to 0db) I am sending:
176 99 1
176 98 17
176 6 107 (0 db)
176 38 107 (to push the MSB all the way up)

Does this make sense? Am I doing this correctly? I won’t be in the studio until tomorrow to test this, but I’m a total newbie with the NPRN stuff…

AH!! OK-I just switched my Midipipe to display HEX instead of Dec, and so not I am seeing 63, 62, 06, and 26. It also cleared up what the BN means-it was in HEX and was refering to the midi channel being sent. The only area of confusion I have now is that I’m not sure if the “ID” written in RED in the manual is in HEX or Dec. But I can check that in the studio tomorrow….wish me luck!

[Andreas]

Maybe some more explanations, but I’m not in reach of my desk so I can’t test.
As you already know there are four MIDI events to be sent to control a fader. Each such an event is constructed from three bytes containing data.
The first byte contains the so called MIDI Status Byte, defining the meaning and number of the following bytes. The Status Byte itself contains two informations. The upper four bits define the command type (like Note ON, Note OFF or, in this case, Continuous Controller or CC) and the lower four bits specify the MIDI Channel on which both partners commununicate. There are 16 MIDI channels available so 16 Devices could communicate through the same physical MIDI cable (well, we’re on USB, slightly different but the protocol still has this information). The MIDI channel is encoded in the bottom four Bits. This is the N of BN. The B specifies a CC message and encoded in the high four bits of the first byte. So valid values will be in hex B0h … BFh or 176..191 in decimal. I’ll denote hex numbers with a lowercase h. So 176 actually means B0h, a CC message on MIDI Channel 0. Should be OK.
The second byte of CC events specify which “controller” should be controlled. Regular MIDI controllers are Volume (7) or Hold pedal (64 resp. 40h). There are also some special “controllers” which effectively extend the range of possible 127 controllers to some 16.000, this is done using Registered and Non-Registered Parameter Numbers or RPN resp. NRPN. To address such an “extended” parameter two CC messages need to be sent first, the 99 and 98 (63h and 62h) CC messages. The meaning of this NRPN numbers are totally vendor specific, the Qu uses the coarse number (63h resp. 99) to specify a channel and the fine number (62h resp. 98) as a Parameter ID of that channel. Parameter ID can be a Fader (17h resp. 23), Pan (16h resp. 22) or PEQ ON/OFF (11h resp. 17) etc.
There is a table at the end of the Qu Mixer MIDI Protocol Document for these parameter numbers, physical channels, for example, start at 32 (or 20h).

So:
176 99 1 -> B0h 63h 01h
176 98 17 -> B0h 62h 11h
would control PEQ ON/OFF on FX Send 2, to address the fader you probably want to use:
176 99 32 -> B0h 63h 20h
176 98 23 -> B0h 62h 17h

After sending the NRPN address (Fader on Channel 1 in this case), the new value needs to be send using another special CC, the Data Coarse CC 6:
176 6 0 -> B0h 06h 00h : OFF
or
176 6 107 -> B0h 06h 6Bh : 0dB
looks OK.

The last Event, which uses the Data Fine CC (38 resp. 26h), does not send the lower bits of that parameter, but specifies some sort of sub-target for that parameter. In case of a fader this will control whether you’re addressing the LR fader or send to a mix for example. This is named the VX value in the spec. To address the LR fader, you need to send a 07h:
176 38 7 -> B0h 26h 07h

To control the Send to a particular mix you’ll need to use ID 20h (or 32 decimal) and specify the target as the VX parameter. So, controlling Channel 7 on Mix 4 should be something like:
176 99 38 -> B0h 63h 26h: CH=38/26h, Channel 7
176 98 32 -> B0h 62h 20h: ID=20h, Addressing SEND
176 6 107 -> B0h 06h 6Bh: Value=6Bh, 0dB
176 38 3 -> B0h 26h 04h: VX=3, Mix 4

Hope this helps to clarify things.

Edit: Fixed Channel Numbering

[Mbirame]

Hi Andreas,
Thanks very much-it does clarify things! I did manage to finally get things working today after a full day of tweaking on it. On stage, I am primarily using Ableton to send all the midi information to the QU-16, so I did come across a few interesting issues that I had to overcome:

There were a few weird quircks that I had to deal with by using one macro knob in Ableton to control whether I was adjusting the L/R or the Mix control, but once I wrote a little Applescript to work some magic, I finally got it working. Now that I’m working with the NRPN a bit, it seems like you could really make a deep controller for your DAW (much deeper than what is currently offered) and maybe rival some of the higher-end controllers. I wonder if track select would change the NRPN value of the eq that is being tweaked for example so that you could select a new track in your daw and use the focus would switch so you could use the eq based on what track you are on.

[Andreas]

Glad you got it get working!
Just realized that I did a mistake with channel numbers, they’re actually starting at 32 resp. 20h. I’ll correct that in my post above. To address channel 7 message must B0h 63h 27h not B0h 63h 07h.
You’re totally right that the native MIDI implementation is way more powerful that the HUI emulation offered in the DAW driver. This is ok for DAWs which can’t be configured but obviously is limited to the possibilities of the HUI protocol.
For the reasonable request to let the Qu selection follow the DAW the Qu MIDI implementation actually misses some “Select physical Channel” command which could be send from the DAW. Maybe PAFL Select could be used for that porpose.

[dpdan]

Andreas, man you know some stuff 🙂

[Andreas]

…at least I think to… 😉

[dpdan]

ha ha ha

[Author]

Posts