Debunking peak levels in mastering…

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[andrepinheiroPinealGenial]

Humility is the sign that I'm on the right channel. Thanks man

[ProductionAdvice]

I completely agree, at 96 kbps the codec artefacts massively outweigh the extra clipping distortion. It might be worth doing the same test @128 kbps, but even there it could be tough to hear.

Fwiw I got 4/5 on headphones, but here’s the thing - it could actually be easier to hear on the YouTube stream because of the extra layer of encoding (!) - clipped material is harder to encode a clean result from.

You also made it super-hard for yourself by blind testing with only a few attempts, though. Blind testing is really difficult (and fatiguing), even with stuff that’s reasonably easy to hear. In fact, maybe I should do a video on how to blind test effectively, hm…

One easy suggestion to try - train yourself sighted, first. Listen to A, listen to B, figure out what you think the difference is, and try and check you really can hear it before going into blind comparisons. Also for distortion, headphones can be easier than speakers, because even tiny head movements can introduce apparent tonal changes (which is how binaural works) which can distract our focus.

Overall though I agree that -1 is a good safe choice, and this is why I suggest -1 dBTP as a great rule of thumb. It’s not foolproof, but for most material at not-insane LUFS levels, you’re unlikely to get any audible problems, even at low data-rates.

[lusid_music_uk]

I’d be interested to hear this same test without true peak enabled. Also love the humility on being able to do an actual blind test and fail! Love that. No BS here. Why you’re one of my favourite people to learn from.
I couldn’t tell either but that’s likely because I was listening through YouTube’s codec on an iPhone 😂

[LETTMusic]

I personally stick with a -1dB ceiling, because even at that, I still run into pretty noticeable artifacts on things like Soundcloud. The problem is, the way these platforms cause your data to be lossy, it's not just simply hard clipping at 0dB, or intersample peaks getting chopped at lower resolution. Different streaming platforms compress your audio differently. It's not just bit depth crushing. Some platforms start cutting the very high end, people have found that YouTube will roll off as much as everything over 16000Hz (which some people confuse themselves with after doing YouTube to MP3 and think the file was actually mastered that way). Some platforms might compress out side information and be more mono, so if you push your mix/master too wide, some of that information may get lost upon compression. So on top of a safe ceiling, I think it's important to make sure your master passes a mono test, and that the high end doesn't have too much buildup.

What I've noticed that's worse than 'distortion' in uploading to some platforms is really bad compression artefacts, that tends to happen in the high end around hats/cymbals. They kind of come off as harsh ticks or squeaks, or the top end just sounds phasey altogether. I think what happens is if a platform applies a steep/brickwall high end cutoff, that's going to introduce a crazy phase shift, which can lead to resonant boosts which magnifies with distortion/clipping.

Another thing to consider for people who do audiovisual content is to not only consider a safe ceiling for audio exports, but also for their video exports. So if you take a song and put it into something like Adobe or Davinci Resolve, to make sure you have a limiter or something in the video export itself to ensure a ceiling there, because few platforms screw your audio up more than YouTube, Facebook, Reddit, Instagram, etc.

I think ADPTR Streamliner is a great plugin that gives you a breakdown of how every streaming platform compresses audio files, and shows you that kind of 'metered' breakdown if you're on strong desktop connection or poor mobile quality, etc. Good companion plugin to Ozone's codec features.

[fivebyfivesound]

Functionally speaking, I think it’s less important whether unwanted clipping can be heard on studio monitors in a treated environment than it affecting the sound on systems where it will have more of an impact on the overall listening experience. For example, I use my phone and a certain set of earbuds for the “is it clipping too much” test.

Also, like others have stated, listening zoomed in on a short loop may be less useful than zoomed out over a longer segment and listening general “bite”, “brightness”, “crunchiness” etc …b/c that’s how audiences listen.

Appreciate the analytical approach 🙏🏽

[americanantagonst]

I won the null test 4/5, even after YouTube CODEC, but it wasn't easy. I specifically identified the differences, which was a very subtle crunchiness when the kick hit. I do have a headphones on though, which helps in many many blind tests. Good video, thank you for sharing!

[h-voltage]

Dancing to the delta of hard clipping. Pretty avantguard of you! 😂

[NINETYSIXMUSIC]

Hey, I've just seen your older video about this same topic where you end up auditioning -0.4 as having the least audible artifacts for the clipping.
There, you make a strong conclusion to use a different celeing for different material.

Could you explain what happened between then and now? Did your research/testing back then not check out?

[NeoTraditionalSpain]

Great video as always!! This is such valuable info, and really worth thinking about. FYI I was able to hear a difference 4 out of 6, from the in built speakers of a mac pro 15"
I found it in the vocal and verb tails. Thanks a lot for your work, it helps us all!

[zandycookitup]

I think there’s something wrong with your routing and it makes it hard to pick out the differences.
You send to NULL the signal that already is lossy to both raw and clipped aux (it seems to me that you’re only trying to see how bad converters would react, but we must remember that a pro grade studio has good converters which will make this as smooth as possible)
I think raw aux should receive the studio quality (wav) and the clipped to have ozone with 96kbps and the standard clip.
Please reply if I’m wrong.

[Rndmondomdon]

Got all right. It is subtle but noticeable.

[Chiefmonks]

Well done, love these tests and observations!

[DJ_Honesty]

The difference is obvious, but hard to say what sounds better.The vocals sound a bit softer and more natural on the raw version. The clipped version has some kind of enhancing effect on the vocals. Can be perceived as a good thing....That Hofa blindtest thing is great, have to get it. Thanks for another great video!

[DavidPeck]

Why leave in a distortion when it can be easily avoided by slightly lowering your ceiling? I doubt anyone could pick out a undithered master in a blind test either, but we do it to achieve the best possible result.

[VinceJackson]

In my studio the clipped one sounded a tiny bit brighter maybe harsher & the none clipped sounded smoother. Surprised but I got them all right :). Thanks again your videos make me so much

[albertoluciani]

Honestly i could hear a difference in all the A/Bs, but i couldn't really tell if one version sounded better than the other

[saturnine]

Great video! Thanks for addressing directly something I commented on in a previous video. Seems like -1 is best for avoiding artifacts almost completely but I feel safer about going to 0.

[themattprofessor]

Interesting test, useful data for mastering, what are you using to monitor codec conversion? Have you tried the Sonnox one.
I was surprised re the Hofa tests, I think I got 4 out of 6. But surely the point is, even though the difference level was 60dB down, and maybe “inaudible” to most people, what is the issue with having a TP of -1dB or even a bit less. All streaming services normalise to a LUFS value of between -13 and 15. Surely the job of a mastering engineer is to translate what the mix engineer intended, but fix any obvious issues that can be done at mastering without lowering the quality. So perhaps a comparison test worth doing would be to look at the difference file between a track mastered to -1dbfs and 0dbfs. As if this is greater than -60dbfs clipping difference then your argument about leaving TP at 0dbfs is valid if on the other hand it is lower then mastering to -1dbfs would be more accurate.

The other point I was going to mention, do your same listening tests on mastered piano music, I think you will find the differences more marked sonically.
Feel free to point out any errors in my logic, as I am always willing to learn.
Really interesting channel am enjoying watching your videos.

[FlashRecordsStudios]

Maybe I'm missing something :) Why not to follow general recommendation of -1 dB True Peak? From my experience the issue with fast peaks is not when a master file gets uploaded/converted to Spotify, YouTube, etc. Even if it is lossless. Audible clipping might accrue on consumers D/A converters. Smartphones and laptops is the good example. So -1 dBTP is for downward SRC and to protect customer's D/A.

[Rolanoid]

Just listening on my phone and $40 Sony consumer headphones the clipped version had less transients and was slightly duller. I could hear it every time. Perhaps you'd hear it on cheap headphones?