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Wide double tracked guitars, polarity? Amp Sim & Guitar Effects Plugins
Old 19th September 2011
  #61
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"Elvis Christ" is right on this one. I never heard a guitar player double himself so perfectly that it cancelled, and I've never heard it from engineers in big studios. in fact I believe it's impossible with a guitar. The imperfect nature of the instrument is it's charm.

If you want a wider stereo image, detune the guitar by a few cents for the second track.
Old 19th September 2011
  #62
Quote:
Originally Posted by Liquid360 View Post
"Elvis Christ" is right on this one. I never heard a guitar player double himself so perfectly that it cancelled, in fact I believe it's impossible with a guitar. The imperfect nature of the instrument is it's charm.

If you want an even wider stereo image, detune the guitar by a few cents for the second track.

Yup, it ain't going to fully cancel, but there can be some canellation.

As in comb filtering etc.

I am really super surprised nobody has ever run into this before.

The detuning thing is a better bet, yes.

john
Old 19th September 2011
  #63
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Quote:
Originally Posted by NEWTON IN ORBIT View Post
I believe it. Maybe your performance are not tight enough?
Well, I panned both guitars hard left/right and after the audioquanizising it was so tight, that 30-50% of the notes indeed sounded like mono from the dead center. Problem was: The same thing happened after switching the phase of one guitar! So I don´t hear any difference, not even subtle.

I don´t doubt that there is a difference. At least the waveforms are different. To me it is not audible, but if I where you and if I where sure to hear that different (and like it) - I would keep on using that phase switch and don´t care what other people say.

Regards,
Lars

Btw: "Tight" and "my screen name"? I don´t see any connection, actually that´s more like an antithesis.
Old 19th September 2011
  #64
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In mono you may get a comb filter effect, sure. Same with synthesizers. A person who has tracked guitars much more than I has suggested using two different guitars to avoid this.
Old 19th September 2011
  #65
Vogon
Guest
I'd think that one has to look at what varies when parts are doubled...
The timing of the pick hitting the string/s.
The speed of the pick and the resulting excitation/impulse of the strings.
How much the string is stretched and therefore pitch shifted when it's released.
The resulting phase of the fundamental. (and of each note in a chord).
The resulting phase and amplitude relationship of all the harmonics.

Enough variables? I think a robot would have a problem creating a phase locked signal across all frequencies. For a whole beat.
I remember trying polarity a few times on HPan guitars many moons ago, and not bothering since.

Also, the MS thing... If I'm not mistaken - the sound of the (say, Guitar 2 M+S=L and -S=R will be a polarity inverted pseudo stereo.
When mono'd I'd think one would lose the volume/mix balance of the guitars?

> To be honest, I'm not knowledgeable enough about sound to explain why the instruments seem to move even further outside the field when the phase is flipped,

That would be because effectively, a negative version of one side signal is added to the opposite side.
If you added a positive (non inverted) duplicate to the opposite side, the signal becomes centred, right between the two speakers...
So with MS processing on LR signals, as you bring up the S, it simply adds more of the opposite polarity to the other sides. To the listener, in the right coditions, the origin of the signal appears to shift further beyond the speaker as the inverted signal is increased.
Dupe a stereo recording, invert it (Channels and polarity) and bring the fader up, it will get wider.
Old 19th September 2011
  #66
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There can be some amount perceivable of tonal cancellation on GTR tracks even with different performances. Fact.

I am not surprised that a percussive or palm-muted gtr exhibits no cancellation. Try it with big, sustained, wall-of-sound power chords.

If you double a gtr track and change absolutely nothing between the 2 performances except for the performance itself, there will likely be some "coincidental" tonal re-inforcements and cancellations in the 2 waveforms when summed to mono. And then if you flip one of them, the cancellations will become reinforcements, and vice-versa. NO one here is saying there could ever be a complete cancellation. Agreed that even the world's best player could not acheive that.

But if you deny that seemingly unrelated signals can reinforce or mask each other in certain ways, then you are denying the very existance of the science that brings you such things as MP3, ATRAC, and other psycho-acoustic technologies.

Last time I checked, those things exist.

Elvis Christ and others in this thread are confusing
"unlikely to make a huge difference"
with
"scientifically impossible"
Old 19th September 2011
  #67
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Kiljoy's Avatar
 

Quote:
Originally Posted by Vogon View Post
Dupe a stereo recording, invert it (Channels and polarity) and bring the fader up, it will get wider.
...and this for the most part is what stereo widening plugins do, which in my experience and opinion are the last thing you should use on hard panned guitar doubles due to the mono incompatibility and other issue around that (mp4, m4a encoding etc.)
Old 19th September 2011
  #68
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Kiljoy's Avatar
 

Quote:
Originally Posted by TRJanuary View Post
If you double a gtr track and change absolutely nothing between the 2 performances except for the performance itself, there will likely be some "coincidental" tonal re-inforcements and cancellations in the 2 waveforms when summed to mono. And then if you flip one of them, the cancellations will become reinforcements, and vice-versa. NO one here is saying there could ever be a complete cancellation. Agreed that even the world's best player could not acheive that.
What I hear is that there is as much reinforcement as cancellation when they're in-phase but just as much reinforcement as cancellation when out of phase; essentially sounding identical.
Old 19th September 2011
  #69
Gear Nut
 
Loflyinjett's Avatar
 

I decided to try it out and I have to say I do in fact notice a slight difference. I'm not sure if I LIKE the difference but I do hear it. I've attached two clips for comparison. 1 is the standard clip and 2 is with the right side flipped.

The clip is a rhythm guitar track from one of my bands songs. Heavily distorted punk guitar with pretty good double tracking.
Attached Files

1.mp3 (1.21 MB, 131 views)

2.mp3 (1.21 MB, 133 views)

Old 19th September 2011
  #70
Gear Addict
 

for the hell of it, i tried the test. i tracked 2 heavy guitars (distorted, by request), playing downtuned power chords (by request)...these were the conditions suggested by my "adversaries" in which it could be heard most clearly. both were tracked identically as possible through softube metal amp room, thus minimizing any changes between the 2 takes besides my very minor human error (i played them tight).
there is no difference. i tried flipping polarity on one channel panned hard left and right, and summed mono. there is no difference. i looked at my paz frequency and phase meters. there is no difference. i even rotated phase on one channel 180 degrees using a demo of voxengo pha-979 (nice plug-in). there is no difference...to the ear or my meters.
just try it.
i can post audio files if someone doesn't mind giving me a few tips on the easiest way to post them here.
anyways, it's been fun debating this. thanks...except to the guy that told me to pee on an electric fence!
Old 19th September 2011
  #71
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slaves666's Avatar
I get phase issues when singers double their vocals. Sometimes its too good and starts to sound crazy and I have to use a take that is less close to the original.

Im gonna check out this guitar idea tomorrow....but I can see how it is possible. If the phase is opposite on a "chug" that attack might sound different.
Old 19th September 2011
  #72
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doug hazelrigg's Avatar
Quote:
Originally Posted by Kiljoy View Post
OK, so I just tried phase inverting one of the double tracked guitars in this here song I'm mixing, and yes they're pretty damn tight. WOW, the effect wasn't subtle at all, in fact, it did absolutely NOTHING to the width, imaging, centre cancellation... No perceivable effect what so ever.
I believe it's more a matter similar sound (frequencies) than tightness. Did you change the tone at all?
Old 19th September 2011
  #73
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Quote:
Originally Posted by Loflyinjett View Post
I decided to try it out and I have to say I do in fact notice a slight difference. I'm not sure if I LIKE the difference but I do hear it. I've attached two clips for comparison. 1 is the standard clip and 2 is with the right side flipped.

The clip is a rhythm guitar track from one of my bands songs. Heavily distorted punk guitar with pretty good double tracking.

Thanks for giving us the PROOF that there is a difference in sound. Very easy to tell one from the other.
Old 19th September 2011
  #74
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doug hazelrigg's Avatar
Who on "my side" of the debate in this thread said ANYTHING about them COMPLETELY cancelling out? If the two tracks were identical, they wouldn't cancel, they'd REINFORCE and sound like they were emanating from the center. Then, if you flipped the phase on one channel, it would get really thin sounding (ideally, if you sum them to mono you'd have silence). I mean, just try it: record a track, copy it, and pan them L&R. Tell us where it sounds like it's coming from, an whether it sounds louder

Again, it's NOT the sameness that causes this phasey quality, it's the differences, however subtle. It's the same when you multi-mic an instrument; quite often the two recorded waveforms are slightly misaligned time-wise, and you get a bit of phase cancellation (hence the 3:1 rule). And I repeat: although it doesn't happen often, I've seen more than once a situation where the two takes WERE very close, and the problem wasn't cancellation, it was the OPPOSITE -- a loss of separation and clarity. Sometimes flipping phase on one channel helped, but usually we had to just do another take.


Also: it's more pronounced on instruments that have more highs than an overdriven guitar cab typically does

Oh, maybe I should add... I'm no fan of flipping phase to achieve width -- especially on heavy guitars... sounds TOO phasey and thin. Actually, I think I stated this earlier
Old 19th September 2011
  #75
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doug hazelrigg's Avatar
Quote:
Originally Posted by Vogon View Post
Also, the MS thing... If I'm not mistaken - the sound of the (say, Guitar 2 M+S=L and -S=R will be a polarity inverted pseudo stereo.
When mono'd I'd think one would lose the volume/mix balance of the guitars?

> To be honest, I'm not knowledgeable enough about sound to explain why the instruments seem to move even further outside the field when the phase is flipped,

That would be because effectively, a negative version of one side signal is added to the opposite side.
If you added a positive (non inverted) duplicate to the opposite side, the signal becomes centred, right between the two speakers...
So with MS processing on LR signals, as you bring up the S, it simply adds more of the opposite polarity to the other sides. To the listener, in the right coditions, the origin of the signal appears to shift further beyond the speaker as the inverted signal is increased.
Dupe a stereo recording, invert it (Channels and polarity) and bring the fader up, it will get wider.
I believe everything you've written above is 100% correct.
Old 19th September 2011
  #76
Gear Nut
 
Kiljoy's Avatar
 

Quote:
Originally Posted by Loflyinjett View Post
I decided to try it out and I have to say I do in fact notice a slight difference. I'm not sure if I LIKE the difference but I do hear it. I've attached two clips for comparison. 1 is the standard clip and 2 is with the right side flipped.

The clip is a rhythm guitar track from one of my bands songs. Heavily distorted punk guitar with pretty good double tracking.
I'm gonna go out on a limb here but that doesn't sound like a double track, this sounds like the same take through 2 different amps (or amp sims).

Edit: In fact, now after two more listens I definitely think it's one take processed differently and panned.
Old 19th September 2011
  #77
Gear Nut
 
Loflyinjett's Avatar
 

Quote:
Originally Posted by Kiljoy View Post
I'm gonna go out on a limb here but that doesn't sound like a double track, this sounds like the same take through 2 different amps (or amp sims).

Edit: In fact, now after two more listens I definitely think it's one take processed differently and panned.
While both takes are from amp sims, I make our guitarist do both sides on different passes. I've never liked the sound of the "Same take, two amps" method. If you listen closely you can hear him switch chords a little sooner on one side when the part gets moving quickly.
Old 19th September 2011
  #78
Gear Addict
 

attached are 320 mp3's of files done the way i mentioned earlier:
1. track 1 the guitars are hard panned. the take on the right rotates 180 in phase using voxengo pha979. i used a demo, so the audio drops out briefly every 30 seconds.
2. same as take 1 summed to mono
3. both takes are hard panned. the take on the right alternates randomly between polarity and reverse polarity.
4. same as take 3 summed to mono.
both were tracked using softube metal amp room. exact same preset. i kept the parts as simple as possible. you will hear some slight timing discrepancies....i did only one take of each and had a few vodka drinks when i did this last night, but the parts are simple enough and tight enough to illustrate my point.
so, tell me....do you hear any change at all in either hard panned or summed mono? does the cancellation or reinforcement of anything change when the phase or polarity does? do you hear any change in the center or the width on the hard panned takes? put it on your meters....is there any change?
Attached Files

phase180rotatepha979hp.mp3 (2.41 MB, 146 views)

phase180rotatepha979mono.mp3 (2.41 MB, 110 views)

phasealternatehp.mp3 (2.41 MB, 149 views)

phasealternatemono.mp3 (2.41 MB, 108 views)

Old 19th September 2011
  #79
Quote:
Originally Posted by Segovia View Post
Well, I panned both guitars hard left/right and after the audioquanizising it was so tight, that 30-50% of the notes indeed sounded like mono from the dead center. Problem was: The same thing happened after switching the phase of one guitar! So I don´t hear any difference, not even subtle.

I don´t doubt that there is a difference. At least the waveforms are different. To me it is not audible, but if I where you and if I where sure to hear that different (and like it) - I would keep on using that phase switch and don´t care what other people say.

Regards,
Lars

Btw: "Tight" and "my screen name"? I don´t see any connection, actually that´s more like an antithesis.

OK, two things, I am not a proponent of flipping the polarity switch in this case. Just to be clear, I don't do it.

Second the screen name thing, I was thinking Andre Segovia this guy, and I figured if you follow in his footsteps, the playing would be tight:

Andres Segovia - Sarabande and Gavotte (J.S. Bach) - Guitar video


Sorry for making an error.

john
Old 19th September 2011
  #80
Quote:
Originally Posted by Vogon View Post
Enough variables? I think a robot would have a problem creating a phase locked signal across all frequencies. For a whole beat.
I remember trying polarity a few times on HPan guitars many moons ago, and not bothering since.

Right, and I don't do it either, it effs up the sound to me.

However, people can and do get really close to doubling exactly, and when the phase is flipped, it can be an issue.

This is why I don't.

Hey if this dude can do this, somebody can certainly lock well enough for a 1/4 measure or something to cancel some when polarity is reversed. No robot here. Some musicians practice with the same intensity.

Samurai cuts pellet In half with sword - YouTube
john
Old 19th September 2011
  #81
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Quote:
Originally Posted by Loflyinjett View Post
I decided to try it out and I have to say I do in fact notice a slight difference. I'm not sure if I LIKE the difference but I do hear it. I've attached two clips for comparison. 1 is the standard clip and 2 is with the right side flipped.

The clip is a rhythm guitar track from one of my bands songs. Heavily distorted punk guitar with pretty good double tracking.
Clip 1 sounds better, fuller.
Old 19th September 2011
  #82
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pasarski's Avatar
 

Quote:
Originally Posted by slaves666 View Post
I get phase issues when singers double their vocals.
Maybe you're confusing pitch issues and phase issues? There simply can't be phase issues with two separate takes. Same goes with guitars.

Human ear is amazing though. I just tested flipping the other side of double tracked stereo backing vocals and I think I can hear the diffrence. Sounds clearer maybe, you could almost say wider, wow!

I think it has everything to do with the bleed from the cans though. I think it's the same with guitars. The bleed from the cans and from the control room to the recording room cancels when flipping the phase.
Old 20th September 2011
  #83
Gear Nut
 
Loflyinjett's Avatar
 

Quote:
Originally Posted by Liquid360 View Post
Clip 1 sounds better, fuller.
I agree that it sounds better, but I think clip 2 could also work depending on the mix it goes into. To my ears the center got carved out a bit which gives the impression of slight widening. When I tried it on the full mix I really couldn't tell if I liked it or not but definitely freed up some room in the center.
Old 20th September 2011
  #84
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Quote:
definitely freed up some room in the center.
Well, I'm by no means the best engineer, but I use EQ for that and not phase tricks.
Old 20th September 2011
  #85
Gear Nut
 
Loflyinjett's Avatar
 

Quote:
Originally Posted by Liquid360 View Post
Well, I'm by no means the best engineer, but I use EQ for that and not phase tricks.
You can change the perception of panning with EQ?

I'm not saying I liked it, just sharing what I heard.
Old 20th September 2011
  #86
Gear Addict
 

As someone who loves gimmicky **** that isn't too gimmicky and obvious in the mix, basically as a result of being forced to do Radio Style Mixes that apparently throw a kitchen sink's worth of gimmicky **** into the mix, let me just say that this trick I am in love with and if you try it and it doesn't work for you, fine.

It works for the people it works for.
Old 20th September 2011
  #87
Deleted 6ccb844
Guest
End of the day this is a proven method, that if done right can have very desired effects.

Look at the SOS manual, it will guide you how to do it correctly. If done wrong it will cancel out if done right it will sound excellent.

There is no rulebook for music and mixing, there are guidelines and best practices but ask any engineer worth his salt... They will have at least give it a go at some point or they even may use it, doesn't mean it's wrong or right and it also doesn't mean that people will like the effect..

Even if you manage to get it without mono cancellation, you may punch a massive hole in the middle of your mix making it sound quite detracted from other instruments.

Imaging can also be widened further at mastering when you split the mono and side information and add more depth..

Just see what works for you and if it gives you what you want then excellent
Old 20th September 2011
  #88
Quote:
Originally Posted by Elvis Christ View Post
attached are 320 mp3's of files done the way i mentioned earlier:
1. track 1 the guitars are hard panned. the take on the right rotates 180 in phase using voxengo pha979. i used a demo, so the audio drops out briefly every 30 seconds.
2. same as take 1 summed to mono
3. both takes are hard panned. the take on the right alternates randomly between polarity and reverse polarity.
4. same as take 3 summed to mono.
both were tracked using softube metal amp room. exact same preset. i kept the parts as simple as possible. you will hear some slight timing discrepancies....i did only one take of each and had a few vodka drinks when i did this last night, but the parts are simple enough and tight enough to illustrate my point.
so, tell me....do you hear any change at all in either hard panned or summed mono? does the cancellation or reinforcement of anything change when the phase or polarity does? do you hear any change in the center or the width on the hard panned takes? put it on your meters....is there any change?
OK, not to be a pita, however this should be mentioned:
You used the 979, which is supposed to overcome this exact problem we have been talking about. The plugin is not mere polarity reversal.

If you want to do the test, please try again with just the polarity switch, as this is what we were discussing no? Or did I miss something.
Thanks,
john

PS.. not sure it makes any difference at all, but I NEVER use dsp guitar tones, always amplifiers.
Maybe you guys are not experiencing it to the degree that I am...I have no idea.

Apologies, but even still, those clips sound wierd as hell to me (still not phase coherent or something?), and IMHO would not end up on any recordings I know of.

Am I tripping here?

It sounds like an old POD or something.
No offense.

Thanks for taking the time to do the test.
john
Old 20th September 2011
  #89
Gear Nut
 
Loflyinjett's Avatar
 

Sounds just fine in the full mix, nobody has ever complained and the album has sold well in it's various formats. The guitar tone is from POD Farm with a very ****ty $75 tele rip off :P It's punk man, it's not supposed to sound good.
Old 20th September 2011
  #90
Quote:
Originally Posted by Loflyinjett View Post
Sounds just fine in the full mix, nobody has ever complained and the album has sold well in it's various formats. The guitar tone is from POD Farm with a very ****ty $75 tele rip off :P It's punk man, it's not supposed to sound good.
Sorry, post not directed at you, but at Elvis

I'll check yours out.

john

edit, yours are much better sounding...sorry, no offense elvischrist.

edit 2: You wouldn't have had to tell me, and I would have known which is the fliiped one.
Sorry, sounds ...err, not so hot. That's why I don't do it.

One is ok though man.
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