The FIRST Step to Mastering a Song: Fixing Phase Rotation | Mastering Masterclass Ep. 4

[@iZotopeOfficial]

Thanks for featuring RX!

[@ADAMAudioBerlin]

Thanks for watching, guys!

[@thegroove2000]

Amazing tools thanks team. Very talented.

[@ADAMAudioBerlin]

Thank you for watching 👍

[@a3axon]

run izotope and Adam monitors ❤ great tools.

[@joannem3051]

What specific software is he using to do this?

[@AndrewMcMillenium]

With all my respect I have to say that in the video, where the beginning of the track was analyzed for phase rotation - the whole track was selected, that's why it showed +34 degree several times. Some sounds, mostly acoustic ones, are asymmetrical by nature. Imagine hitting a drum membrane with a stick. The first half-wave is the biggest in amplitude, because it's caused by the stick (or hand) directly being in contact with the membrane and moving it much deeper/further than what comes next. Every movement coming next is smaller and smaller in amplitude and if you analyze the whole drum hit sound - it will have a skew from the center line. Regarding the difference - many people say you don't hear a difference, BUT. People who work for example with car audio know that there is a difference. If you wire all the speakers in a given car in a wrong polarity - you'll have less punch, because the first movement of speaker membrane goes inside instead of outside. And all this phase correction thing (which I was using in the past too) is a wrong thing to do, because it messes with the original natural sound. It won't change RMS, frequency response, but it will sound differently. If you say "pumpkin" into a mic - it will be asymmetrical, because of how much the mic membrane is being moved by the air bursts. But it should be that way! And after using RX adaptive phase rotation for years on podcasts I finally stopped doing that and it sounds much better and natural. So, the only good thing about phase correction is that you can squeeze more volume out of it.

[@doingittodeath]

I totally agree with you...BUT I think, that some of the information given in this video may be helpful for some situations like the one mentioned in the video with the trombone solo. If you can't really make something out of a stem or so because of these phase rotation problems, this feature in RX could be really helpful for not distorting the sound. I myself had a vocal some days ago where the waveform looked really weird to me because there was more information above the center line than below. I only read something about phase rotation in the tooltips of one of the compressiors found in TDR Limiter No. 6 and couldnt really understand what phase rotation is until I saw this video now. But I think it would've helped me in a way if I knew about this topic earlier. Unfortunately these scientific and technical topics don't really get discussed that often.

[@haidar6280]

Wow. This has completely opened my eyes to something I've never known about or thought of before. It's so rare to find completely new information in this engineering world 6+ years in. Gem of a video guys. one love

[@ADAMAudioBerlin]

So happy you've enjoyed it! Make sure to let John know how much you've appreciated his knowledge! We simply captured it

[@RonnieVaiArovo]

Totally agree 👍

[@cleantones]

6 years. :) I'm 25 years in and still learn plenty. Maybe not on this video but it's a constant learning and evolving craft.

[@ahriik]

@@cleantones Right? If you're not still learning new things regularly at only 6 years, I'd be awfully concerned.

[@DerperyPooslinger]

In 2013-2014 I got a chance to work with John in studio A. I couldn't believe the atmosphere that room has, and John's enthusiasm when it comes to explaining the science behind his craft. Quality guy and quality work.

[@davidasher22]

Wow! It’s been a while since I actually learned something new from an audio engineering video on youtube. Faith restored..

[@ADAMAudioBerlin]

Thanks for watching David! So happy you enjoyed it.

[@Barncore]

Wow i've been doing audio for 8 years and i've never heard of this. Really grateful to have been exposed to this nugget! Thanks

[@ADAMAudioBerlin]

Thanks for watching!

[@Vospi]

but note that phase rotation is not "free" in terms of how it sounds (although it's very transparent), which wasn't mentioned in the video.

[@JAROCHELOcesarcastro]

I'm not a mastering engineer but knowing this info definitely helps a lot. Thank you!

[@Arch-Peggio]

Just when I think I'm starting to get over the first hurdles of learning to mix.. I find this mind blowing technical wizardry.

[@sqcaraudio]

My take is that it's using an FIR algorithm to shift phase tilted from the highest frequencies to the lowest. So the 20kHz is delayed by say 30 degrees and then less at 10kHz down to no shift at 10Hz. You can do this with Meldamedia "free phase". The reason you can't do adaptive on main mixes is that it may introduce pitch artefacts due to the delay changes. The key term here phase is meaning delay but they don't say FIR time domain manipulation. So less delay at lower frequencies. Hope that helps. You could run two files against each other in Rational Acoustics Smaart and see what phase plot x y tilt they are using.

[@beatchildproductions]

Mix With The Masters... TAKE NOTES! This is how you make educational content.

[@ADAMAudioBerlin]

Thank you for watching 👍

[@Jarxiel]

Thanks ❤

[@ADAMAudioBerlin]

Did you know about the importance of phase rotation already? Let us know 👇

[@maxduncan4473]

I read that it's applied in radio processors (Orban, etc) to optimize the available headroom, just as you're doing here in a mastering context. I did read also, though, that it has an interesting drawback for material which has been deliberately clipped (ie: with the wave flat-topped). Sometimes the flat-top is rotated around to being a straight line more in the middle of the waveform; it looks like a scar or a drop-out. (I'm not sure it would sound like a drop-out though; it would still just sound like the distortion that it is, right?) I don't work in mastering anymore, but I still do it sometimes when I'm working on unevenly-recorded vocal podcasts. Because the presenter is moving back-and-forth in front of the microphone, you end up having to apply heavy compression or limiting to even out the volume, with all the usual drawbacks. But male voices, particularly, are very asymmetrical, so applying phase rotation to them can mean you don't have to hit the compressor as hard.

[@chopsoe]

The fact that it gives more headroom for volume optimisation afterwards is so logical and I don't know why I never really thought about it before... Good stuff!!

[@ADAMAudioBerlin]

Glad you liked it 👍

[@cassio_zambotto]

yes, dc offset can steal significant headroom when you need it! great knowledge sharing!

[@JoelWard1]

Wowza. I had absolutely zero clue that this was a thing. Geez, I'll be having trouble going to sleep this night knowing how many masters I could've saved just by having the feintest clue about this....

[@intoalter]

This is going to be a GOLDEN series!!! I would love to see a course regarding Audio Engineering through some subscription, It would be a absolute game changer, because the quality you guys give us is absolutely amazing.

[@ADAMAudioBerlin]

Thank you for watching and so happy you're enjoying the series. No need for a subscription, we're happy to make this for everyone to watch!

[@intoalter]

@@ADAMAudioBerlin love you guys!

[@ADAMAudioBerlin]

❤️ Thanks for watching!

[@TomWa]

Wow! I wish I had known about this sooner. I'm working on a project where, from a stereo mix, I'm removing vocals, correcting them, and then replacing them back into the vocal-less stereo instrument stem. The RX8 music rebalance algorithm works WAY better once the rotation (which was off by quite a bit) is corrected. Thank you!

[@derekrushe]

45 years old, in the industry years, never even heard about this until today. Thanks

[@ADAMAudioBerlin]

Thanks for watching, Derek 👍

[@audiokemestry]

Great info!! I have bumped into this problem many times...and addressed in different ways....but I never knew what it was called and never knew RX could fix it! Lol. Thanx much

[@kelvinfunkner]

WOW! I've been in this industry for a long time, and have never run across this in my own recording/mixing/mastering sessions, but I've seen others ask about it and didn't have a clue what was going on! Thanks for sharing this!

[@footsandersen]

John is amazing. I went to him for mastering and got a mixing mentor!!!

[@ADAMAudioBerlin]

Love it! Thanks for watching, Keith.

[@banyanmusicofficial8899]

Incredibly helpful and simple to understand. Thank you!

[@ADAMAudioBerlin]

Thanks for watching, Banyan! Glad you enjoyed it

[@LiamBradburyMusic]

I'd love to sit in a room with this guy and chat for about 2 days straight

[@ADAMAudioBerlin]

Absolutely, Liam 👍

[@skk6811]

A hardware company giving out professional courses for free. I'm sold.

[@ADAMAudioBerlin]

Glad you enjoyed it thanks so much for watching!

[@davelordy]

The reason the phase keeps showing you +34° is because you keep analysing the same audio - the whole track - when you think you are selecting a specific part, you are only zooming in on that part, not selecting it . . . . keep up : )

[@Rene_Christensen]

And phase is per frequency so what is even the 34 value?

[@davelordy]

@@Rene_Christensen 34° is how far out of phase something is, so (obviously) 0° is completely in phase, and 180° is completely out of phase. So if we were comparing two pure sine waves, it would be like the starting point of one of the sine waves (the point at which it crosses 0dB (or 0V / or 0°) is aligned with the second wave that is already 34° into its cycle.

[@Rene_Christensen]

@@davelordySure but he is not looking at single sinusoidal, he is looking at a piece of music. I have a PhD in acoustics and work with signal processing daily and I cannot see any sense in what he is doing.

[@Todzuum]

@@Rene_Christensencan you go deeper into why you said this?

[@Rene_Christensen]

@@Todzuum In the frequency domain, everything revolves around sinusoidal signals that started forever ago and will go on forever. This is where we can talk about the phase of each sinusoidal, as each frequency component ("phasor") then has a complex amplitude with positive magnitude and a phase. If you analyse a more involved signal that is described via several (possibly infinitely many) sinusoidals at each their frequency, it does not make sense to talk about a single phase. There is no "total' phase to discuss then, only phase that typically varies over the frequency spectrum. You can of course have the trivial situation of zero phase (a wire) or 180 degree phase change over all frequencies (flipped wires; polarity flip), but the 34 degrees make no sense here.

[@feinklangmastering]

This is gold content! Thanks for this in depth specific look at this difficult topic.

[@ADAMAudioBerlin]

Thank you for tuning in, Johannes!

[@LOLCoolJ]

So ideally we'd do this before mixing?

[@vadimmartynyuk]

These tutorials from Adam Audio are really great, every tutorial is very useful.

[@ADAMAudioBerlin]

So happy to hear it, Vadim appreciate the kind words!

[@soundtoys795]

would it be a better to check phase rotation on individual tracks, to minimize the cumulative effect in a stereo mix??

[@TjMoon91]

Doing it on a stereo file doesn't create an audible change. However, if you did it on each track individual track, the phase shift will mean those tracks will now stack up differently. If you have already carefully layered sounds together like multiple snares, or layered synth bass lines, applying phase rotation on these individually will potentially change how they sound when mixed together.

[@soundtoys795]

​@@TjMoon91 So the correct way to do it is to fix the phase on all tracks before doing any mixing

[@TjMoon91]

@@soundtoys795 yeah I suppose so. Two different sounds both with symmetrical waveforms can still result in an asymmetric waveform when mixed together, so I’m not sure you’re achieving much. Maybe if you have a particularly uneven stem like a lead vocal it might be worth doing it with those select tracks.

[@parentteachernight]

@@soundtoys795 In that case you'd be altering the phase relationship between all multi-mic'd sources. This is a solution in search of a problem.

[@IvanoIcardiOfficial]

Pure wisdom... thx for sharing this!

[@ADAMAudioBerlin]

Thanks for watching, Ivano!

[@edulimamusic.oficial]

John you are amazing. Thanks for existing!

[@martijn_nl]

The phase tool in RX also has an adaptive mode. Is there a good reason for not using it?

[@soundkillah]

Am so happy I arrived here 🤗🤗. Never thought there was anything like that at all.

[@ADAMAudioBerlin]

We are happy you arrived, thanks for watching 👍

[@GrumpyGr3g]

Video is "old" but wondering, why not use the "adaptive" mode ? I did several tests on different types of music, some works perfectly fine with the "suggest" while some other performs better (phase wise) in "adaptive" mode, especially when there a massive difference on transient. The suggest mode does not change a lot, the adaptive seems to really center things up better. Any where to find out more infos about what's really going on behind these two different modes ? Cheers!

[@alan_gleeson]

from the manual "Adaptive phase rotation is best used on vocal material, as it can occasionally yield pitch artifacts on musical material." So in the always use your ears.

[@musicbyea474]

This info is so valuable!! Thanks so much, John 👍🏻

[@Rhuggins]

This was the best series you ever did @ADAMAudio

[@burns46824]

Very interesting. If you're mastering to make things loud, this makes sense to do. If you're making quiet masters, I don't think I would do the extra processing.

[@panorama_mastering]

Great video guys; top job!

[@ADAMAudioBerlin]

Glad you enjoyed it!

[@m.i.stapes]

John Mayfield is one of my new favorite people.

[@rarelycomments]

How does waveform asymmetry relate to phase? What does the Izotope algorithm do, in signal processing terms? What does he mean by a "false digital value"? Aren't a lot of real instruments naturally asymmetric? i.e. kick drum, trumpet etc. Does removing this asymmetry audibly change the signal?

[@TjMoon91]

It doesn't audibly change the signal, it just gives you a lower peak value. Which means you can push the signal louder before hitting the threshold of a compressor or limiter.

[@michaelgraflmusic]

I think they just picked some guy off the street, gave him a list of buzzwords and a ten-minute introduction to Ozone and then filmed his improv performance. I have the same questions as you do, because none of this made any sense. He even used percent to describe the phase rotation instead of degrees. Pretty sure the phase optimization tries to find the position with the least amplitude so the limiter has to work less or something like that. It has no effect on DC-offset.

[@TjMoon91]

@@michaelgraflmusic 100% = 360 degrees, 50% = 180 degrees, 25% = 90 degrees. I'm sure you can work that out.

[@andreymosin1884]

I've been looking for solution for ages! Thank you!

[@ADAMAudioBerlin]

Thanks for watching, Andrey 🙏

[@MichaelSchuerig]

I don't understand how this is related to phase. What I understand from John's description and see in the graphs is that he is removing a DC offset. How does phase get into this?

[@lkadshglkhvani]

Based on the RX documentation, it seems like the tool is using phase shift to change where the digital samples are taken, giving you slightly more headroom, but afaik that wouldn't change the true peak maximum.

[@ADAMAudioBerlin]

Hi Michael, great question. Like the comment below, the answer comes from the Izotope manual: We are balancing asymmetric waveforms by rotating signal phase. Rotating the phase of a signal changes its peak values but doesn’t change its loudness, and otherwise has no audible effect on the signal. Asymmetric waveforms can occasionally occur in audio such as dialogue, voice, and brass instruments. Making the waveform more symmetrical gives the signal more headroom.

[@matrixate]

That's what I thought but this is not a DC offset.

[@rocketman374]

Michael, how do you fix DC offset? The answer is, usually with a very low hpf. That hpf isn't linear phase, so it induces a phase change in the material. Dan Worral has a good video on that...

[@MichaelSchuerig]

@@rocketman374 Dan has a lot of good videos, can you point to the specific one?

[@allourep]

Anybody know what caused the Trombone recording to have the phase rotation issue to begin with? What can the engineer do on his end to fix it once noticed during the session?

[@TWEAKER01]

@@ShroomJesus exactly. It's not a "problem" at all. Applying the "fix" to a full mix will always affect other elements.

[@rikkshow]

It is typical for brass sounds. By getting the waveform to center, you don't change the sound, but you reduce the digital peak value in one channel, thus getting more headroom.

[@allourep]

@@rikkshow So recording in 32 bit would be a way of avoiding this issue in that case?

[@zsteinkamp]

hell yes! thank you for this. today I learned!

[@dunkeldeutsch]

Thank you so much!! Can you or anyone in the comments recommend a Plugin for Phase Rotation (using Cubase) - Thank you!

[@gbebici]

this phase asymmetry its a natural capsule's behavior, once you're pushing more than pulling it. When you're recording a Brass, for example, the blow will always push the mic (if the player is standing on front of it). Not saying that it must not be corrected later. Am i right?

[@matthijshebly]

This is more about even harmonics.

[@PremJHans]

Thank you John and Adam Audio for this video. New thing learned.

[@ADAMAudioBerlin]

We are glad to hear that 👍 Thanks for watching

[@BrandonTmusic]

I would love to know WHY this happens to wav files in the first place. What causes a digital recording to have a lot more information above or below the center line? Is it faulty recording equipment? Electrical issues?

[@tightsnare]

Dc offset due to additional voltage in the circuit i believe :)

[@gbebici]

Its a natural behavior once you're pushing more the capsule than pulling it. When you're recording a Brass, for example, the blow will always push the mic (if the player is standing on front of it)

[@matthijshebly]

It's not specific to digital recording. It has to do with the presence of even harmonics (e.g. 2nd harmonic) in the signal, causing an asymmetric waveform. The phase between fundamental and these harmonics determines how high the peaks will be, without changing the sound. What he does in the video changes this phase, thereby lowering the peaks.

[@TWEAKER01]

it simply shows a natural acoustic event for mostly positive going waveforms (read: acoustic pressure).

[@JiihaaS]

Nothing weird about wind instruments causing the waveform to be lopsided like that. Air blowing from the instrument into the mic capsule will push the diaphragm back, and the diaphragm's position is directly related to the produced waveform. Same happens often with human voice, since there's blow of air involved, especially on plosives.

[@LaminarSound]

This is the first ive learned about phase rotation. Ive seen asymmetrical waveforms for years but never noticed any audible issue with them. However, i wasnt really *listening for it. I still dont quite understand why this happens though. Is this something that happens when the signal is being converted to digital? Or is this issue inherent in the source signal?

[@peadybeatz6721]

Can somebody give an answer on this question? I'd like to know too :)

[@Tibbon]

Similarly, I'm curious about the cause.

[@TjMoon91]

It's just something that happens with different phase relationships between the fundamental and it's harmonics. Nothing to do with digital audio, we just weren't aware of it before digital because we weren't looking at waveforms. There's no "audible issue" except that the peak value is higher, even though it isn't any louder. Which mean's you can't turn it up as loud before hitting the threshold of a compressor or limiter.

[@reedtaylor4846]

@@TjMoon91That is correct. This is the answer. Just about every horn part I've ever recorded was positive heavy and looked funny on the screen. It's the timbre of the instrument itself causing it. Interesting though, is this lesson about how these waveforms create false peak levels that steal some of the mastering engineer's working headroom, I never considered that aspect.

[@kelainefes]

@@reedtaylor4846 some vocal tracks have this issue here and there. I think it happens when there's a strong 2nd harmonic, which always causes asymmetrical waveforms. Some plug-in emulations of valve equipment will do it too, but I think actual valves will do the same. But I think there might also be different causes for this.

[@ronaldanderson9263]

Is this not the same as DC offset? Cakewalk, what I use has a DC offset removal which should center the waveform around 0.

[@naughtyducky6325]

It’s not the same thing, when you have DC offset the waveform is perturbed from the Center line, fixing DC offset moves the waveform back to the Center. An Asymmetrical wave form isn’t symmetrical on both sides so while it may be on the Center line it’s positive amplitude is different from its negative amplitude.

[@matrixate]

I read about this exact problem many years ago in a discussion by the assistant engineer to Dolly Parton's mastering engineer. He said this was the first step even before they did any processing.

[@justtosharefiles678]

This was actually a really awesome video thanks for sharing bru

[@shevyjohn9308]

Would this then be process using analog or this is a printed track from analog processing before using a digital limiter ?

[@ASJerrell]

This is incredibly cool and rather fresh information. Thank you!

[@ADAMAudioBerlin]

So happy you enjoyed it, Andrew!

[@ADAMAudioBerlin]

Glad you enjoyed it, Andrew 👍

[@Hexspa]

This almost creates more questions than it answers. I’d like to see a way to achieve this without RX specifically. An industry-wide standard definition would be good too.

[@Tibbon]

I don't think there are any ratified industry standards on it.

[@rafriley6993]

there’s a free plugin by air windows called DC offset. It doesn’t the the exact same thing but you can shift the entire waveform higher or lower which can help if you have asymmetric peaks

[@Hexspa]

@@rafriley6993 Right. But I think they were saying that this isn't DC offset. Ableton has that built into Utility and I think Meldaproduction has it in their MUtility plugin also. DC offset is a pretty generic thing and that's why I was asking what's going on here.

[@anthonycarr3495]

@@Hexspa I'm pretty confident this its exactly the same as DC offset - no idea why he has decided to call it phase rotation

[@Hexspa]

@@anthonycarr3495 Weird, huh? Never tried correcting DC offset on a master but it makes sense. I mean 'phase rotation' :)

[@JohnDoe-wl8ti]

Would you do this in the beginning or at the end of your master right before the final limiter(s)?

[@fermendespaula]

John Mayfield! Great professional and an awesome guy!

[@ADAMAudioBerlin]

He really is! Thank you for watching, Fernando 👍

[@MarioTorre]

Doesn’t that alter the stereo panning?

[@Ruekeen777]

wow! that's some valuable info.

[@HollywoodRecordingStudio]

Excellent explanation about the how the imbalance issues impact RMS.

[@ADAMAudioBerlin]

Thank you, Meghan! Glad you liked it 👍

[@chrisgabriel6397]

How do you apply this phase rotation in Adobe Audition?

[@Dan_Tan_Music]

Thanks for a great topic. I get asymmetric waveforms a lot when recording piano, phase rotation can help to improve the sound here.

[@ADAMAudioBerlin]

Thank you for watching, Dan! glad you liked it 👍

[@sinsoftherich]

I don't think any of us realized we'd become scientists when we first got into music lol

[@chadmichael_]

Thank you for a genuinely helpful video.

[@js5633]

Always wondered why the top was larger than the bottom or vice versa. Excited to do this with RX 😎🙏👍

[@ADAMAudioBerlin]

Thanks for watching!

[@BronsonOsborne]

enjoyed this thanks for sharing

[@tracker87]

Magical information. Really grateful to @adamadio

[@ADAMAudioBerlin]

Thanks for watching!

[@JSBallard]

Does it make it sound better?

[@davearooney]

so, at 1:50, he says it's 38 degrees out - where is he seeing that number? It says 34 in the Phase dialog box.

[@MelodicDreamers]

This is extremely helpful. Thank you

[@MOSMASTERING]

Can you explain how this sort of 'issue' occurs in the first place? I assume it comes from the microphone or multiple mics summed together? If I'm working entirely in the box using software instruments, synths and samples, this isn't going to happen, right? Can you even hear the difference between a piece of audio with an asymmetric waveform? What sort of benefit am I gaining, apart from, I guess - ability to master a track louder because you've moved a louder 90 degree wave phase moving closer to the zero crossing point? What about DC Offset in some microphones?

[@ADAMAudioBerlin]

Hi @MOSMASTERING! Thank you for your questions, we unfortunately cannot answer them since we made the video a long time ago, we suggest to contact John directly for any questions. Thanks for understanding 🙏

[@AndrewMcMillenium]

I'm not John, but I can help you with that. Some sounds, mostly acoustic ones, like guitars, percussion, human voice, are asymmetrical by nature. Imagine hitting a drum membrane with a stick, the first half-wave is the biggest in amplitude, because it's caused by the stick (or hand) directly being in contact with the membrane and moving it much deeper/further than what comes next. Every movement coming next is smaller and smaller in amplitude and if you analyze the whole drum hit sound - it will have a skew from the center line. This doesn't usually happen in synthesized sound as much especially the closer you go to a sinewave. Regarding the difference - many people say you don't hear a difference, BUT. People who work for example with car audio know that there is a difference. If you wire all the speakers in a given car in a wrong polarity - you'll have less punch, because the first movement of speaker membrane goes inside instead of outside. And all this phase correction thing (which I was using in the past too) is a wrong thing to do, because it messes with the original natural sound. It won't change RMS, frequency response, but it will sound differently. If you say "pumpkin" into a mic - it will be asymmetrical, because of how much the mic membrane is being moved by the air bursts. But it should be that way! And after using RX adaptive phase rotation for years on podcasts I finally stopped doing that and it sounds much more better and natural. Regarding the benefits - you get less distortion when applying dynamic processing (compression, limiting). In some cases of course phase correction is needed and as you mentioned DC offset - it's absolutely needed. Because in this case the waveform is shifted to one side by constant voltage applied to the signal.

[@MOSMASTERING]

@@AndrewMcMillenium Thank you so much for your detailed response, appreciate that a lot. What's your take on this - I don't know if it's real or if it's placebo - but I often listen to two sounds together in isolation and hit the invert phase button a few times in the Cubase channel strip.. and just by ear, I decide whether they sound better together or not. Even if its very slight, I believe in all the 1% differences to your mix all adding up.. Obviously, sounds that have a lot of low-mid overlap (around 200hz-ish on snares, for example) will obviously have some punch added or subtracted if a sound has any frequency overlap in that range. But - I apply this check to every sound in a general group of similar sounds (drums, synths, vocals etc.) no matter where they are in the spectrum.

[@AndrewMcMillenium]

@@MOSMASTERING It's not placebo, it's 100% real and objective. Here's a simple explanation. Imagine a kick drum of a drum set. If you invert the phase, then the first couple of milliseconds of initial air compression will transform to decompression. Overall it will sound almost the same, but you you can feel it if you just put your hand on the speaker (or subwoofer if you have one). Sometimes RAW audio has wrong polarity from the start, so you checking it is actually a good thing.

[@MOSMASTERING]

@@AndrewMcMillenium Bear in mind. I'm not talking about phase flipping drums or kick and bass to fit together etc.. I really mean - phase correction *in general*. Because, I fully understand and can easily hear it is not placebo in the case of drum or sounds with a low frequency fundamental. The lower the frequency, then obviously the more pronounced the potential for a frequency overlap.. I'm referring to my micro-adjustments when it come to phase flipping comparing AMY and ALL sound-to-sound? Example; synths or sounds that have fundamentals above perhaps - 2000hz - with information content up to and above 10k. If I take a lead pluck sound and play it against a pad, for example. I flip the phase back and forth and just pick the one I think sounds best. Also, I have a great plugin called PHA by Voxengo that allows complete phase rotation degree by degree, not just 90 degrees at a time.. This is incredible for EDM when matching up the kick and bass and dialing it in perfectly. I am an audio engineer, so I fully understand the concept of speaker cones moving and what phase actually represents. I just wondered if anybody else goes as 'in depth' as me when it comes to phase across the entire freq. spectrum.

[@bonesnoopd]

Is this the same thing as removing DC offset?

[@QuiethouseRecording]

No

[@QuiethouseRecording]

No, DC offset has to do with the waveform sitting above or below the center line. This is the waveform not being symmetrical on the center line.

[@bonesnoopd]

@@QuiethouseRecording got it, thanks alot

[@FrequencySummoner]

I'm not sure it makes sense to refer to this as "fixing" or "correcting" phase rotation, as though some phase relationships are inherently "wrong". What you are doing is optimising the phase for digital headroom. What does this process do to transients? Don't people intentionally use all-pass filters to smear transients in time? How is that avoided here? (I'm not a professional audio engineer, just trying to make sense of this from a physics perspective and an artistic perspective.)

[@johnmoney910]

Thank you!

[@wbtbwb18]

What is the phase software? Does ableton have a stock plug in for this?

[@fredbeckofficial]

Izotope RX

[@wilcandou]

Now THAT was a great little bit of information right there. I had notice this looking at my waveform. It's interesting how this could happen on a mono stem though. It's something you can't really hear, but it makes a whole lot of sense in correcting the DC offset. Nice pickup. 👍

[@ADAMAudioBerlin]

Thanks for watching!

[@mcsweet1966]

Hello, Thanks for a very intersecting Video, Can you explain what would creat a unballance like that at the recording/mixing stage and is there something we can keep our eyes (ears) on so it would not append.

[@maxduncan4473]

It just occurs naturally in some types of instruments. You can't hear it.

[@matthijshebly]

Even harmonics. The phase between those and their fundamentals determine the peak levels.

[@scoremix8556]

Very good. Side note ; brass is always “ top heavy”.

[@zayin_beats517]

Just a quick question. Isnt rms like the average volume of an audio track? So how come that by fixing phase issues you get headroom but rms is the same?

[@iamsyntact]

this is incredible. I can't tell you how many times I have a sample or instrument that's way out of balance and before now I had no idea how to fix it. so many times I've heard "you can fix this with a highpass filter" but this is absolutely not always the case. thank you sir

[@MistaMin]

Great video!

[@ADAMAudioBerlin]

Thank you for watching, Mista!

[@matthewv789]

Super interesting and something I was not at all aware of. I will be going back and immediately checking a project for phase issues. Very well and clearly explained. (And now wondering if there’s anything else I might have missed that nobody else seems to talk about!)

[@ADAMAudioBerlin]

Thanks for tuning in, Matthew! All the best 👍

[@raybeeger1529]

Is DC Offset the same or what is the difference?

[@eccentricworx]

Very useful to know!

[@RocknRollkat]

Hello John, Excellent presentation, thank you. I remember phase rotation in relation to A.C. motor theory. What you're explaining here is what we call 'D.C. Offset'. Your thoughts when you have a minute, thank you. Bill P.

[@davelordy]

Yeah, I always see this issue as DC offset too, I interpret it as a 'stuck' sine-wave, which you can get rid of with a hi-pass filter (set as low as it will go).

[@RocknRollkat]

@@davelordy The hi-pass filter is a 'must' for getting rid of U.L.F. rumble, etc., but it will not 'center' a signal around the '0' voltage point. Most DAWs have a 'D.C. Offset Removal' function that will 'center' the signal around the '0' point AND remove the D.C. offset after it has been recorded. Some DAWs allow you to remove D.C. offset during recording, folklore says 'Don't do it", wait until AFTER the track is recorded, then fix it." Bill P.

[@davelordy]

@@RocknRollkat Yep, a hi pass _will_ remove a DC offset ('centre' the signal around 0v) think of a DC offset as a very low sine wave, in fact a 0Hz sine wave, now lets image this sine wave is at something like 45° in its phase, so about 70% between 0v and 1v, as it's at 0Hz it is 'stuck', that is to say it's no longer oscillating, at 0Hz it becomes a DC offset (it's a DC offset at all parts of its phase except for 0°), so one way to remove this DC offset is to use a hi-pass filter, you want to set it as low as you can go as you don't really want to alter the sound, 10Hz or 20Hz is usually as low as an EQ or LPF will go . . . this removes the DC offset.

[@RocknRollkat]

@@davelordy Dave, here's the problem. If a sine wave has zero frequency it also has zero phase. It's direct current.

[@davelordy]

@@RocknRollkat _"If a sine wave has zero frequency it also has zero phase"_ It will have a _fixed_ phase, you can literally measure it, it will only be zero at 0v, everywhere else, from -1v to +1v it will be at a fixed (unchanging) phase, so for example a DC offset of +0.5v will have a phase of 30° (sin(30°)=0.5), or a DC offset of +0.1v will have a phase of ~5.7° (sin(5.7°)=0.1) . . . etc etc. Don't take my word for it, try it for yourself, take (or make) a signal with a pronounced DC offset, apply a HPF (set it as low as you can), render the result and see for yourself, the DC offset is gone, you've removed the 0Hz fixed carrier wave.

[@kick4ss4life]

This is the only video/piece of information I could find so far that approaches this topic in mastering, for the rest it's all about fixing it mixdowns, but unfortunately I'm in no position to be able to fix the problems in the mix. Since I'm doing an assignment for school that's solely focussed on mastering, I must ask: If there is a lot of Anti-Phase issues going on in the Mixdown/Premaster you're mastering, how much should/could one do to correct this? Especially if you don't have a plugin like RX at your disposal for example? I have analyzed professionally mastered files with the PAZ meter, and a lot of times I still see a lot of spikes in the Anti-Phase Region. Anyhow, I'm supposed to be in the final stage of the project, but this keeps breaking my head. Thanks in advance to anyone who might give me some clarity on this!

[@machoman7655]

Basically, phase rotation is to algin your track from causing phase. You can also take care of phase in the mixdown stages when you are mixing down drums, bass, guitars, etc. Also, when you bounce a track down it never aligns up perfectly, that will also cause phase. For example, if you bounced a beat down and want to use it to record. You have to make sure you put in back in phase before you use it. This is one of the hidden gems that no mastering engineer will tell you. What's even better he gave up the magic number of -2 that will give your master a smooth feel. Basically, if you don't algin your tracks and take care of phase, it doesn't matter how good your mix and master is it will sound bad.

[@arthurcerqueira696]

So, it would not make sense to do this on an already mastered song right? Since just heard about this concept and I already have some songs "done".

[@snubdawg1386]

wow nice tip thank you ...but why should it be -2? ...i tried this on different mixes and masters and after rendering it's - 2 or sometimes +2 ....first i thought to recognize a pattern that only the masterings and loud sources will be rendered to +2 but it also happens to low mixes ....should i correct it with the sliders to -2?

[@tonal.states]

I think it's more of a "the lower the number the better" kind of case so -2 is WAY better than say +34 or -50, always going for something close to 0 there. That's what I got, could be wrong.

[@mistati8000]

Thanks for the great advice! I have a few (possibly stupid) questions: 1. Is it recommended to fix the phase issues for every single track of a mix individually or for the overall mixed track? (I am asking because Mr. Mayfield only shows a single track in this example that looks like a complete mix) 2. If the answer to question 1 is "for each track individually", is it also recommended to fix the phase issues for *vocal* tracks individually? 3. Is anyone familiar with alternatives to the RX Audio Editor's Phase Algorithm shown in this video to fix phase issues? I saw that RX 11 Standard version starts at 330€ which is a bit much for a hobby - home studio producer, given you are only interested in the phase fixing functionality. Any help greatly appreciated, thanks in advance :)

[@m.i.stapes]

Holy crap!! I did not know that. Super interesting!!

[@ADAMAudioBerlin]

Glad you enjoyed it, thanks for tuning in!

[@oscarpatxot659]

As a Latin producer working with many brass instruments I have notice this all the time. I just why it is so common for brass to have the rotation wrong

[@semilumi]

I have noticed this too. I would assume it has to do with the high pressure wind energy coming off the instrument and hitting one side of the microphone membrane... But the picture is incomplete, got to go to google...

[@parentteachernight]

Because the timbre of the instrument creates an asymmetric waveform. It's not a problem in need of correction!

[@rikkshow]

Air pressure I think

[@RonnieVaiArovo]

mind-boggling 😇

[@jefjaeger]

So what caused it in the first place?

[@Almostbakerzero]

while this is interesting, i dont quite understand how it works. now the issue here is that a waveform is for some reason offset from the digital zero point (which is basically equal to an analog signal thats offset by a positive or negative DC voltage). however, i wonder what fixing this might cause. he gives an example of a very small part thats being fixed. in order to fix just a part of the track, its necessary to offset the part so its in the middle. but at the point where the "non-offset" transitions into the corrected part, you automatically have some sort of audible transition. either a click, or RX has some sort of smudging feature to mask it. when editing the whole track, you could offset it without having any clicks. But since i would assume that the track has some "real" silence in it, (beginning or end), this silence would be offset to a point where it is not really zeroed but rather above or below zero.

[@studiodsr]

Is this beneficial to do on every single track before mixing, or is that overkill?

[@drecckk8464]

well it depends, are your recordings heavily out of phase? if so, then yes you should fix that or else your mix will lack dynamics and headroom, but if not, then its fine enough to just fix it in the mastering process. thats why the pay for good recording engineers.

[@markdeffebach8112]

How is this different than DC offset? (In my previous career I designed mediamatrix cobranet products from 98 to 08)

[@andreyaek2266]

Yeah, this is my question also. When I’ve seen a waveform skewed to the positive or negative side I’ve always understood it as a DC issue, not a phase issue. High passing below 20 (with a good filter), or otherwise removing DC fixed some such problems for me before, but I guess there might be more to learn here.

[@markdeffebach8112]

Well I did my own research and it seems that the phase of each frequency component of the audio signal is shifted rather than shifting the entire waveform and this returns symmetry to the zero point.

[@shotaro_music7625]

Very Helpful!😊 Thank you🙏🙏

[@ADAMAudioBerlin]

Glad you enjoyed it!

[@snapascrew]

I always love reading the comments from the experts 😂😂😂

[@methodofkolishin]

Wow! That's kinda of a game changer!

[@ADAMAudioBerlin]

Thanks for watching!