Output Routing for Logic Pro X (Using Output 2 Vs Output 1 for Stereo Mixing) - SOLVED (Accessibility Settings)

hensh!n_vfs

Inspired
I'm wondering how everyone is routing their Axe FX III within Logic Pro X when using the Axe III as their interface. I know a lot of people use additional audio interfaces in conjunction with their III, but I prefer to keep a simple setup. I spend the majority of my time mixing, playing over backing tracks, and recording (in that order). So for several years (circa 2016 or so), I've sought out the best way to route everything at a relatively even level with the least amount of hassle when going from one function to the other all while using the Axe. Then I stumbled on something. On my Mac when the speakers are routed to Output 2 (Out 3/4 in Audio MIDI) and my Stereo Output in Logic preferences is set to Output 3-4, there is more depth and stereo image than when it set to Output 1 (Output 1-2 in Logic). If I route my Audio MIDI to Out 1/2 and and do any different combination of the settings, guitars that are panned left in my mixes will still come out in the center. Discovering this now has actually helped my mixes as now they translate the way I was hearing them in my head vs how they were actually coming playing through the monitors. I believe I received a similar result via following a thread about routing USB audio to Out 7/8 and using a USB In Block. The only problem with that was changing my settings would interrupt the music (as it was dependent on those I/O blocks).

Currently I'm connected to my Studio monitors (Tannoy Gold 7's) using the XLR Outs of Output 2, and the Humbuster outs of Output 1. This is so I can blend additional processed guitar signal into the monitors as needed when I'm playing over backing tracks.

I tested this at a variety of different configurations such as using the XLR outs of Output 1 instead of the Humbuster outs and still keeping Output 2 via the Audio Midi Setup on my Mac, but the audio in Logic (and other USB audio sources) still lacked the stereo width and depth. I've gone over the manual many times and I can't for the life of me figure out why this would be the case. As I understand it, this was not the intention of Output 2, but I'm simply wondering why that is and if anyone else has played with their routing options to notice differences in stereo field (for audio, not guitar) between the two outputs.

For reference I do have USB Output Mapping 1/2 -> Out 2, 3/4 -> Out 1 however it sounds the same with the other setting as long as I have Output 3-4 selected in Logic.
 
If you pan something in your DAW to the left, but you hear it in the center, then something is configured wrong :). It could be you don't have that output port set to the "stereo" option.
 
It's definitely set to stereo, but I'll play with the wiring again and see if I can get some different results with Output 1.
 
Check your Output modes for Output 1 and Output 2 in the I/O menu. Make sure they're set to Stereo and not SUM L+R.

Also, check your incoming levels on the Meters page of the front panel (page all the way to the right from the Home screen). You can see the USB signal level coming back from the PC there. The USB IN meters should reflect your panning changes in Logic. If you hard pan the output in Logic, but the USB IN meters are still showing input on both channels (USB IN 1 and 3 = left, USB IN 2 and 4 = right), something is not set right in logic.
 
I tinkered with it a bit more and found that routing USB audio through Output 2 gives the stereo depth. Regardless of any settings I configure, any USB audio I tested doesn't come out in true stereo on Output 1. What is strange is there is nothing connected to Output 2 anymore, but when I route everything through Output 2 (3/4) the panning is correct in Logic and iTunes. I can confirm this as well with the USB In Meters. When they show Out 1/2 and the settings are so USB Audio is routed through it, the sound comes out in the middle. However, when I change Audio Midi to default to Out 2 (3/4) and set Logic to Out 3/4, its stereo. This goes for other USB audio as well with sources like iTunes and Amazon music. So basically I followed the advice as mentioned in the manual, configuring my speakers to default to Output 2 and swapped the USB Output Mapping. The manual mentions that USB Audio is added to these Outs, so perhaps it is added via the USB cable and not the XLR cables. Because as of now I have nothing connected to Output 2, yet all of my stereo USB audio is routed there.
 
You'll find the output port modes in the I/O settings. It sounds like you have that set to one of the mono options for port 1. Or you're running that output through the grid by accident and summing it to mono in the grid. Otherwise, it's a defective unit.

P.S. As mr_fender mentioned, you can use meters to help diagnose the problem.
 
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It's definitely not a result of incorrectly configuring the I/O settings (or at least I don't believe that to be the case). Everything is set to Stereo. Out 1/2 is connected XLR to my studio monitors. If I route USB Audio through 1/2 (and confirm via USB In Meters), it is not true stereo as panning doesn't come out correctly (missing part of the signal vs coming out through the correct speaker side). However, if I got into Audio MIDI > Configure Speakers > Output 3/4, and set Axe Edit USB Out Mapping to 1/2 -> Out 2, 3/4 -> Out 1 then viola, stereo image in Logic, iTunes and every other source. It's just odd that nothing is technically connected to Out 2, yet the USB audio still routing through it. I can make a video if need be to demonstrate.
 
It's definitely not a result of incorrectly configuring the I/O settings (or at least I don't believe that to be the case). Everything is set to Stereo. Out 1/2 is connected XLR to my studio monitors. If I route USB Audio through 1/2 (and confirm via USB In Meters), it is not true stereo as panning doesn't come out correctly (missing part of the signal vs coming out through the correct speaker side). However, if I got into Audio MIDI > Configure Speakers > Output 3/4, and set Axe Edit USB Out Mapping to 1/2 -> Out 2, 3/4 -> Out 1 then viola, stereo image in Logic, iTunes and every other source. It's just odd that nothing is technically connected to Out 2, yet the USB audio still routing through it. I can make a video if need be to demonstrate.
Let’s see a video
 
If the USB In meters do not show correctly panned signals between USB out 1 and 2 then something in your OS or Logic is not set correctly. Verify your output settings there.
 
The USB In meters don't show any L/R USB In difference when panning the guitar left or right, it simply plays through the Left speaker (using Out 2) or in the center (using Out 1). When setting configuring monitors to Out 1 the USB In shows USB IN 1/2 as opposed to IN 3/4, which makes sense.

I can make another video demonstrating the same thing in Logic, but I don't see what difference it'll make. Stereo Out 1-2 outputs GTR L to the center whereas Output 3-4 (in Logic, after setting Audio Midi to Out 2), outputs GTR L to the left. But again the USB In meters are the same, it's just outputting via USB 3/4 Vs USB 1/2. I don't know what other OS settings would be involved as I'm simply following the manuals instructions to route USB audio through Output 2, configuring Audio Midi to Out 3/4 (Out 2), and setting USB out mapping from USB 3/4 to Out 1 (since Out 2 isn't physically connected).
 
So now it's working in reverse, so Output 1/2 is in stereo and not Out 3/4. I can even see the results reflected when I hard pan on the USB In. Can anyone tell me what the problem was? I figure it's useful to know for future reference. Literally all I did was go back into Logic, reverse the Output settings from 3/4 to 1/2 and change Audio Midi Config back to Out 1/2. So now it's stere via Out 1/2, but no longer 3/4. I tested this in Apple music as well. There's obviously something here that I'm not quite grasping, and it shouldn't be something as simple as "the output isn't set to stereo" since that was never an issue (you can confirm in the video as well).
 
Ok I think I've figured it out. Output 1/2 is Stereo for USB Audio coming from sources like iTunes. However it is not stereo in Logic, hence I have to configure the Output to 3/4 (Out 2). The video will only show it in Logic, but I can confirm a difference between the two.

 
Ok I think I've figured it out. Output 1/2 is Stereo for USB Audio coming from sources like iTunes. However it is not stereo in Logic, hence I have to configure the Output to 3/4 (Out 2). The video will only show it in Logic, but I can confirm a difference between the two.


You have to tell Logic to capture two channels if you want stereo. You can have it create a single track that has both left/right, or two separate tracks with left in one and right in the other.
 
How is your master buss configured? Is it set to stereo output? Do you have any other busses or sends active?

It also looks like your project is in 44.1 kHz sampling rate. The Axe FX is fixed at 48 kHz, 24 bit, so Logic is having to resample on the fly. That likely has nothing to do with your stereo issue though. Just something to keep in mind if you run into any latency issues.
 
Somewhat simple minded question, but is your track set to stereo in Logic?
Master Out is Stereo. Guitar Input is Stereo. Guitar is outputting to Master Out (which is also set to Stereo).
You have to tell Logic to capture two channels if you want stereo. You can have it create a single track that has both left/right, or two separate tracks with left in one and right in the other.
I don't understand what you're saying here. You can hear in the video if I set the Output to 3-4, the audio is being output in stereo. But if I set it (Logic) to Stereo Out 1-2, Guitar L is coming out in the middle therefore it is not stereo. All audio was recorded using In 1+2.

I just don't understand why I have to route iTunes through Axe Out 1 and it's stereo, then I have to route Logic through Out 2 (3/4) in order to get stereo audio in Logic. I thought the point of using USB Out Mapping or configuring the monitors via Audio MIDI was to change the Stereo Out of System (USB Audio), but it doesn't seem to be the case.

So from what I've been able to gather, USB 1/2 is stereo for USB Audio (iTunes, Amazon Music, etc.). But I have to use Out 3/4 to get my Logic mixes to come out in stereo.

Also from what I understand in Logic, the Output selection does not change the master bus but rather where the master bus is being output (i.e. to send your mix through a different pair of monitors, although I am only using one pair).
 
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The problem is not in Logic. It's on the AxeFX side. Your video didn't show the usb input meters for your mono case, but that's where I would start looking to troubleshoot problem.
 
The problem is not in Logic. It's on the AxeFX side. Your video didn't show the usb input meters for your mono case, but that's where I would start looking to troubleshoot problem.
That's where I'm leaning, but I don't want to be asked to show my stereo outs in Logic anymore or be asked to prove that my guitar was recorded in stereo... You can hear it in stereo when I switch the out to 3/4 instead of 1/2. The next video will show USB In for 1/2, in addition to my
connection.

However, I have a feeling at that point I'll be asked to use XLR for 1/2 instead of TRS. But I've switched XLR between Out 1/2 and 3/4 and it makes no difference. I don't appear to be getting stereo out of Out 1/2 at all (anymore at least). Not sure if it's related to the Mac or whatever else, I'm just trying to figure it out. If the issue goes on after the next video perhaps I'll just send in a ticket to support for assistance. I just wanted to do my due diligence first since I've worked in tech support myself for several years.

 
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Be systematic. You've got a problem, but your videos always manage to miss the most important information :). Somewhere in your signal chain your stereo signal is collapsing to mono. Your latest video should show: 1) Logic's output bus meter, and 2) The AxeFX usb input meters. If the former is stereo and the latter is mono, then you've discovered the location of the problem and you can start hunting for settings that would affect that. Until you pinpoint the location of the problem, your problem scope is too wide for anybody to provide a precise solution.
 
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