Logic Pan values - equal amounts left and right

[ralphonz]

Good morning, afternoon or evening!

I'd just like to know, once and for all, what the score is with the values of the logic pan pot (balance or stereo pan).

We all know that left goes to -64, while right goes to +63.

Can someone confirm that if I want dto pan two tracks equally in the 50% position left and right would the numbers be -32 and +31, or -32 and +32, or -31 and +31?  The problem is you can't divide 63 by two, but you can with 64!  Is exact panning precision just not possible in logic?

I know, use your ears (which I always do) but when you want precision it's good to know these things things and any engineer worth his salt should know the technical specs of the equipment they use.

[des99]

Yes, they are equal. It's just a result of the limited resolution of 8-bit values inherited from MIDI (when there really wants to be 128 positions - -64 -> + 64 including the 0).

Don't worry about the number scale, the actual levels internally are scaled correctly, and this is easy to verify with null tests.

Edited April 27, 2022 by des99

[David Nahmani]

I suppose that because you have 64 values on the left and only 63 on the right, and -64 is the exact opposite of +63, that the precise positions of each increment on either side are not equal. Meaning -32 is not the exact opposite of +32, it would be closer to +31.5. I suppose so, I'm not sure. 

But honestly I don't believe that matters when producing music. Most of the time if you want to pan one signal left and the other right in opposite but equal angles, then two signals are different to start with, which means they'll probably need different amounts of panning in order to be perceived at the same angle on either side of the Stereo field. 

When I get a mix with one guitar panned +37 and the other -37, I know the person who mixed did it by numbers, not really listening. I know their intent was to have the two guitars sound at the same angle in either direction, but it rarely does so. When I close my eyes and balance out two instruments on either side of the stereo field, it's more common to result in values like +39 and -33. 

[fuzzfilth]

9 minutes ago, David Nahmani said:

When I get a mix with one guitar panned +37 and the other -37, I know the person who mixed did it by numbers

This.

[ralphonz]

21 minutes ago, David Nahmani said:

When I close my eyes and balance out two instruments on either side of the stereo field, it's more common to result in values like +39 and -33. 

Assuming your monitor set up is perfectly aligned or your using headphones!  If I get a mix like that I balance out the gains of each side without using the pan pot so that they sound equal, then it is much easier to adjust and control the width of those tracks and also see the width at a glance at the mixer.   Also, by doing this in mono, I'm ruling out the monitors skewing my stereo balance.

One side is always going to be a little bit off from the other side then?  Only having 64/63 increments (rather 100 like "other software") also means that this difference is bigger as there's less degree of precision.

This is really only a problem when mixing at a super high-level and looking for that little bit of extra accuracy.   It's not very exact from an engineering perspective.  Another small reason why so many pros stick to pro tools perhaps?

It'd be easier if the mixer pan pots had the same degree of accuracy or worked on a percentage like the gain plugin.

Edited April 27, 2022 by ralphonz

[fuzzfilth]

I doubt you hearing a difference of 1 pan in an otherwise identical mix. 

Change my mind.

[ralphonz]

18 minutes ago, fuzzfilth said:

I doubt you hearing a difference of 1 pan in an otherwise identical mix. 

Change my mind.

True, I just like to know.  Curiosity more than anything else!

Also, I'm working on a mix today with about 20 backing vocal tracks (don't worry I'm grouping them!) needing to be spread out and it just got me thinking because no matter which value I chose things sounded off to the left or right a little.  I guess I needed that .5 of precision to do what I was trying to do.  The more dense a mix becomes and the more you try to use width the more of an issue the precision of the pan-pots becomes. In the end I just split the difference but I just had to find out what the score was with the pan pots.  

Basically, I'm taking the answer to be "if you wan't to get exactly 50% between centre and right speaker you can't!".

It'd be hard to be a mix engineer without being at least a little bit nerdy...

Edited April 27, 2022 by ralphonz

[David Nahmani]

What I was trying to express is that you're panning different signals, for example two different guitars, they have a different attack, different transients, different frequency spectrum, a different dynamic, and all of these attributes affect how much you need to pan them in order to move them in the frequency spectrum. Where guitar #1 may need to be panned at -39 to be perceived at a certain angle, guitar #2 may need to be panned at -32 to be perceived at that same exact angle. So if you were able to pan the two guitars exactly at +32 and -32, then they would not be perceived at the same angle, guitar #1 would be a little closer to the center than guitar #2.

So if your goal is to have the two audio sources be equally far from the center on either side of the stereo field, then it does not matter that the pan knobs cannot have the exact same positions. 

So in the end in my opinion if your goal is to mix music, at any level of music production you may be, this is a non issue.

[David Nahmani]

4 minutes ago, ralphonz said:

Also, I'm working on a mix today with about 20 backing vocal tracks (don't worry I'm grouping them!) needing to be spread out and it just got me thinking because no matter which value I chose things sounded off to the left or right a little.  I guess I needed that .5 of precision to do what I was trying to do.

I really doubt it. I don't think you would have heard any difference if your pan knobs gave you more resolution. I understand that your brain might be telling you that while you're looking at the numbers on the pan knobs, but I don't think your ears would be able to tell if I had changed on pan knobs from -46 to -48 and Christian had turned the one that you had set on +31 to +29. 

Let me tell you a story about psychoacoustics. I worked in a large recording studio with a chief engineer who was famous for having superhuman ears. Everyone knew his ability to detect the smallest little difference in a pan or fader position, blind. One day we were calibrating the console, and that meant playing a 1kHz sine wave while adjusting a pan knob with very fine amounts until he could detect the sound source coming dead from the center of the stereo field. He positioned his head in between the speakers and closed his eyes, asking one of the engineers to slowly turn the pan knob left and right. Then he started saying "a little more to the left, ok, now a tiny bit more, oops - that's too much, back toward the right, oops... we were almost there, a little more to the left..." And the whole time, the engineer wasn't touching the pan knob, the sound wasn't changing at all. 

[ralphonz]

14 minutes ago, David Nahmani said:

What I was trying to express is that you're panning different signals, for example two different guitars, they have a different attack, different transients, different frequency spectrum, a different dynamic, and all of these attributes affect how much you need to pan them in order to move them in the frequency spectrum. Where guitar #1 may need to be panned at -39 to be perceived at a certain angle, guitar #2 may need to be panned at -32 to be perceived at that same exact angle. So if you were able to pan the two guitars exactly at +32 and -32, then they would not be perceived at the same angle, guitar #1 would be a little closer to the center than guitar #2.

So if your goal is to have the two audio sources be equally far from the center on either side of the stereo field, then it does not matter that the pan knobs cannot have the exact same positions. 

So in the end in my opinion if your goal is to mix music, at any level of music production you may be, this is a non issue.

Maybe it's a workflow difference or I'm not understanding things properly?

Usually I'd pan them to the same position (say -39 and +39) then use the level control and processing (EQ, comp for example) to make sure they sound equal.  So I'm splitting the difference between the left and right channels in the same way with each guitar and evening out its dynamics and frequency with other tools to make sure it balances with the one on the other side.  If the pan pots are equal on each side, it makes adjusting width later much easier.

[des99]

1 minute ago, David Nahmani said:

And the whole time, the engineer wasn't touching the pan knob, the sound wasn't changing at all. 

One of the reasons we can so easily fool ourselves, is that we generally think we're too smart to be fooled...

[ralphonz]

1 minute ago, David Nahmani said:

I really doubt it. I don't think you would have heard any difference if your pan knobs gave you more resolution. I understand that your brain might be telling you that while you're looking at the numbers on the pan knobs, but I don't think your ears would be able to tell if I had changed on pan knobs from -46 to -48 and Christian had turned the one that you had set on +31 to +29. 

Let me tell you a story about psychoacoustics. I worked in a large recording studio with a chief engineer who was famous for having superhuman ears. Everyone knew his ability to detect the smallest little difference in a pan or fader position, blind. One day we were calibrating the console, and that meant playing a 1kHz sine wave while adjusting a pan knob with very fine amounts until he could detect the sound source coming dead from the center of the stereo field. He positioned his head in between the speakers and closed his eyes, asking one of the engineers to slowly turn the pan knob left and right. Then he started saying "a little more to the left, ok, now a tiny bit more, oops - that's too much, back toward the right, oops... we were almost there, a little more to the left..." And the whole time, the engineer wasn't touching the pan knob, the sound wasn't changing at all. 

🤣 Yep, been there too!  In fact, this happens quite a lot on some days.  I'll see how I'm feeling about it tomorrow then...

[fisherking]

i remember walking into a friend's mix session at a major studio in nyc; he plunked me down in the engineer's chair, asked me to listen to the mix.

i said 'it sound's great, but why is it heavier on the left'?

'it's not' said the engineer. 'it's you'.

then someone checked the main monitor amp and discovered... the left volume was up slightly over the right. great moment.

i can hear a .005 difference between left & right panned sounds, and it's upsetting 🤣

(seriously... not...)

[ralphonz]

3 minutes ago, fisherking said:

i remember walking into a friend's mix session at a major studio in nyc; he plunked me down in the engineer's chair, asked me to listen to the mix.

i said 'it sound's great, but why is it heavier on the left'?

'it's not' said the engineer. 'it's you'.

then someone checked the main monitor amp and discovered... the left volume was up slightly over the right. great moment.

i can hear a .005 difference between left & right panned sounds, and it's upsetting 🤣

(seriously... not...)

Well I just found out I've been listening to the mix on my monitors with sonarworks on a headphone profile all morning 😬

[fisherking]

8 minutes ago, ralphonz said:

Well I just found out I've been listening to the mix on my monitors with sonarworks on a headphone profile all morning 😬

my current deal is... if a mix seems off-center, i just move my chair...

[des99]

There's no difference in level between left and right. They peak at exactly the same level on the side they are panned to, and they let nothing through on the other side.

Forget about the numbers, they are scaled correctly internally - fully right is not somehow "less fully panned" than the other side.

If you want to check mid numbers, then they are generally offset by one, so -30/+29 is equal level, rather than -30/+30... The difference between "1" value is about 0.2dB. Whether you can hear that, or whether your audience can, is down to you, but in general, my advice is to mix with your ears not your eyes.

Most people's hearing is not 100% equal either, so you might find that something that sounds balanced to you might not to the next person, as their left/right weighting is different.

 

Edited April 27, 2022 by des99

[ralphonz]

4 minutes ago, des99 said:

There's no difference in level between left and right. They peak at exactly the same level on the side they are panned to, and they let nothing through on the other side.

Forget about the numbers, they are scaled correctly internally.

No no, that's not what I mean at all.  Of course there's no difference between the same signal panned left or right, it would be completely broken if there was.

But if you have two guitars, say they were double tracked, and you pan one hard left and one hard right, because they're different takes there will be differences. To get the mix to balance properly you would adjust the level of one of them so that it sounds "centred" as it were, but wide.  If one was lower it would sound as though the guitar was over to one side instead of equal on both sides.  To the untrained ear you're trying to create the impression that actually there is only one guitar, but sonically it sound big and wide.

Probably poorly explained again, sorry! but hopefully that makes more sense....

[ralphonz]

I should add that the discrepancy comes up when -39 is not the same as +39 (for example), but actually -39 is equal to +38.67 or something!  You follow?  Because there are more increments on one side than the other, they don't match up (127 being an odd number).

 Obviously you could use a stereo plugin insert to set the pan position with greater precision (even the stock gain plugin allows this) and the channel would output the result perfectly as intended.  This is more of a sort of accuracy/poor design sort of thing, by the looks of it to do with some arcane MIDI-compatibility thing (my guess because 64+63= 127).  Indeed, it would make more sense to display -64 and +64 and for logic to do the necessary maths internally.  I'm sure there's a way to engineer it differently to allow for great precision and better UI, but (going by this thread) not essential or something that many users care about.

Not the end of the world, just trying to clarify what I'm going on about!

[des99]

16 minutes ago, ralphonz said:

To get the mix to balance properly you would adjust the level of one of them so that it sounds "centred" as it were, but wide.

Sure, and you'd do that by ear, rather than looking at the pan number. With different takes, they are not going to always contain the exact same audio energy at exactly the same point, so you'd position the pans and levels accordingly. These differences would vastly outweigh the 0.1-0.2dB differences in pan settings.

I know what you mean, but I can honestly say it's never been an issue in nearly 30 years of using Logic for me. If it is for you, you'll have to develop a coping strategy when looking at the numbers, by adding 1 to one side.

Edited April 27, 2022 by des99

[ralphonz]

9 minutes ago, des99 said:

Sure, and you'd do that by ear, rather than looking at the pan number. With different takes, they are not going to always contain the exact same audio energy at exactly the same point, so you'd position the pans and levels accordingly. These differences would vastly outweigh the 0.1-0.2dB differences in pan settings.

I know what you mean, but I can honestly say it's never been an issue in nearly 30 years of using Logic for me. If it is for you, you'll have to develop a coping strategy when looking at the numbers, by adding 1 to one side.

That's the thing, you can add one if it's hard panned right easy enough, but the maths is different if you're panned at say halfway at 32 (or 31.5 hahaha), or panned at +17 or something.

It will likely annoy me forever so my coping strategy will probably more along the lines of take a deep breath and forget about it 🤣

[des99]

2 minutes ago, ralphonz said:

That's the thing, you can add one if it's hard panned right easy enough, but the maths is different if you're panned at say halfway at 32 (or 31.5 hahaha), or panned at +17 or something.

I gave you an example at +30/-30, and it was 1 off in the same way. But I'm not measuring every interval..! 😝

3 minutes ago, ralphonz said:

It will likely annoy me forever so my coping strategy will probably more along the lines of take a deep breath and forget about it

Sounds like a good plan! 😉

[ralphonz]

6 minutes ago, des99 said:

I gave you an example at +30/-30, and it was 1 off in the same way. But I'm not measuring every interval..! 😝

Sounds like a good plan! 😉

For the sake of understanding, I think it's not 1 off.

If -32 is 50% of the way between left and centre, then because it only goes up to 63 on the right, 50% between right and centre is 31.5.  So at half way the difference of one is halved.  I couldn't be bothered to do the maths for +/-30 but you get the idea...  Basically and increment of 1 degree right does not equal an increment of 1 degree left, and furthermore the difference is not going to be consistent, it will be less the closer to 0 (centre) that you get.

Anyway, it really is splitting hairs, I do accept that!

Edited April 27, 2022 by ralphonz

[des99]

28 minutes ago, ralphonz said:

If -32 is 50% of the way between left and centre, then because it only goes up to 63 on the right, 50% between right and centre is 31.5.  So at half way the difference of one is halved.  I couldn't be bothered to do the maths for +/-30 but you get the idea...

Yes, I well understand the idea - which is why I measured it (ie forget what you *think*, *measure* it to be sure) at a midway level I selected at random, and did find as far as the level goes on the meter, it was indeed exactly one off (ie, adjusting it by one value gave the same output level results as the other side.) Like I say, my quick test isn't necessarily representative of all values, it was a quick sample to see what happened there. If you want to measure and test more values to see what the audio results are to give us more real-world data, feel free...

We don't know what internal scaling is used, but I wouldn't get too caught up on the 8-bit value display of the fader, because that doesn't necessarily represent what is happening underneath (typically, in a 32/64-bit float mixer, most values are floats between 0.000.. and 1.000...). Those 128 values of the limited resolution pan knob are mapped onto that range, but not necessarily in a way that directly represents a linear scale according to the 8-bit values. (For a start if it was, the top value wouldn't result in the same 100% panned signal right as the left side, which is easily verifiable - see above).

For me, it's a non-issue - I pan the audio to where I want to hear it, not where the numbers indicate I should put something to be "correct" - but it does crop up fairly regularly over the years (decades now) since Logic added audio to it, and I understand and accept that for some people, the fact that they feel they can't satisfactorily pan something left -30 and right -30 and feel it's "correct" is a niggly and mildy annoying issue.

How do other DAWs map a 128-byte range onto a centre-offset control? Do they just do -63 - 0 - +63 and ignore the extra missing value? Or have -64 - +64 and have no true centre panning value? Or something else?

Edited April 27, 2022 by des99

[ralphonz]

7 minutes ago, des99 said:

How do other DAWs map a 128-byte range onto a centre-offset control? Do they just do -63 - 0 - +63 and ignore the extra missing value? Or have -64 - +64 and have no true centre panning value? Or something else?

I have no idea, in pro tools you have 100 increments on either side.  Even logic's own gain plugin displays a value as a percentage left or right - both being equal with zero in the middle.  To my knowledge logic is the only application that displays uneven values. 

But yes point taken about the internal scaling.  That may well be the case, I will have to test it.  I don't know if you posted the wrong screenshot but it was panned -64/+63 in your post.

Maybe one day they will apply the mapping scale to the value that's displayed on the screen as well as the actual audio just to satisfy the whims of engineers with nothing better to do... Oh no is that me?  I'm supposed to be mixing!

[des99]

8 minutes ago, ralphonz said:

I have no idea, in pro tools you have 100 increments on either side.

Ok, so they have a finer on-screen resolution by the sounds of it. They still have to (presumably) deal with controlling that value via a MIDI control, which is again a 7-bit value (128 steps). (This is why Logic has behaved like this, for legacy MIDI reasons - while they upped the fader resolution to 10-bit, when controlled via regular MIDI it's still 128 steps).

Logic *could* do this, and scale the incoming 7-bit MIDI control to a wider range (it does this for all controller assignments, for example), but perhaps it's a legacy thing, they don't want mess too much with this for fear of changing peoples projects...

8 minutes ago, ralphonz said:

I don't know if you posted the wrong screenshot but it was panned -64/+63 in your post.

Perhaps you missed the point of the animated screen movie - I was showing the pan/level results in the audio signal that happen when you fully pan left (-64) are identical to when you full pan right (+63), proving that +63 in terms of audio is not somehow "less than fully panned because the number is 1 less", and proving that +63 does in fact equal -64 *in terms of the audio results*.

Edited April 27, 2022 by des99

[ralphonz]

1 minute ago, des99 said:

But they still have to deal with controlling that value via a MIDI control, which is again a 7-bit value (128 steps). (This is why Logic has behaved like this, for legacy MIDI reasons - while they upped the fader resolution to 10-bit, when controller via regular MIDI it's still 128 steps).

Perhaps you missed the point of the animated screen movie - I was showing the pan/level results in the audio signal that happen when you fully pan left (-64) are identical to when you full pan right (+63), proving that +63 in terms of audio is not somehow "less than full panned because the number is 1 less", and proving that +63 does in fact equal -64 *in terms of the audio results*.

Oh right yeah, sorry yeah they're the same hard left and right for sure, of that I was never in any doubt.  I thought you were trying to show +/-30 was the same on each side (which it may well be if the values are actually re-mapped behind the scenes).  I'll probably hook up the same test later to see if it is, and if not what the difference is.

Yeah I understand the MIDI thing, it's just hard to accept when nothing else works that way (i.e. the MIDI values are mapped behind the scenes and the actual value is reported on screen in everything else I can think of, hater than it being the other way around) just seems like neglect on the part of the developers from where I'm standing.  I'm sure it's less important to see a MIDI value than a truthful one.

[des99]

8 minutes ago, ralphonz said:

I thought you were trying to show +/-30 was the same on each side (which it may well be if the values are actually re-mapped behind the scenes).

No - I thought I was fairly clear in my above posts, that in terms of signal level, they are in fact off by one at the 30 point I checked... so -30/+29 was the same in terms of signal level, not -30/+30...

You can always send in a Feedback on the issue, but I'm pretty sure it'll be a duplicate...

It's not a case of "neglect" by the way imo, it's a question of juggling many priorities among the resources you have. This is fairly unimportant in the big picture, compared to some of the many other more major things people are complaining about.

But hey, miracles do happen - we recently got an update to *finally* overcome the MIDI channel bottleneck, and people had been asking for that since... ooh at least Logic 2.x... ☺️ ...so you never know!

Edited April 27, 2022 by des99

[ralphonz]

16 minutes ago, des99 said:

No - I thought I was fairly clear in my above posts, that in terms of signal level, they are in fact off by one at the 30 point I checked... so -30/+29 was the same in terms of signal level, not -30/+30...

You can always send in a Feedback on the issue, but I'm pretty sure it'll be a duplicate...

It's not a case of "neglect" by the way imo, it's a question of juggling many priorities among the resources you have. This is fairly unimportant in the big picture, compared to some of the many other more major things people are complaining about.

But hey, miracles do happen - we recently got an update to *finally* overcome the MIDI channel bottleneck, and people had been asking for that since... ooh at least Logic 2.x... ☺️ ...so you never know!

Agreed!  It is somewhere near the bottom of my "List of things I wish they would do".

Thanks for that, saves me doing the test and it's good to know.

All the responses are much appreciated by the way.