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when i mix my music, i always turn down all the tracks faders, so my final stereo head room will be around -20 db. then i add limiter and add something around 14 db , so my final lufs will be somewhere around -6 db (the numbers are not accurate) . but i wonder , if i dont pull down the faders too harsh , so for example my final head room would be at -10 db, then i add 4db with limiter, so my final lufs will be -6 db, is there any difference between these two methodes or they are the same? i mean is there any difference to how much i add db gain when i limiting? (i mean both of times my last lufs is -6 db. ). anybody know? thanks

dana
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  • My guess would be that there is a chance of introducing noise when you "handle" the signal more (as in the first scenario), but I am not an expert in audio! – The Chaz 2.0 Jan 26 '18 at 01:01
  • What’s a luf? Also 20 dB is a lot of headroom and depending on the summing algorithm your software uses you might get better sound quality by pushing it a bit more. What DAW are you using and what limiter? – Todd Wilcox Jan 26 '18 at 06:00
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    Ok, figured out what LUFS means. I’m not sure if that’s caught on in the US yet. I don’t think Pro Tools has a LUFS meter yet. If you have a LUFS meter that reads -6 then that actually sounds really hot. You might shoot for more like -12 to -8. Coming into the stereo bus at -20 LUFS is actually a good idea, in fact if I understand LUFS correctly, audio for film and TV is usually delivered at around -20 LUFS. You might check out k metering also: https://en.wikipedia.org/wiki/K-system – Todd Wilcox Jan 26 '18 at 06:13
  • hi todd.i use cubase and waves WLM pluse for my LUFS. its like RMS but from what i learned its more truthful to human ears than RMS. and you can also use this for broadcasting. they use -23 db for europe music brodcasting. but i only use it for my output loudness measuerment. and i am agree. -6 or -7 db is too hot and it will kill some of my dynamic for sure. but the problem is if i dont make it too loud, it wont be able to compete to other musics, when you listen it on mobiles. – dana Jan 26 '18 at 10:50

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Theoretically yes, they should both give the same results. The only time the limiter should be changing the sound in any significant way is when it is reducing the volume of the peaks. Simply turning the volume down and then back up should not change the sound.

You can verify that they are the same by trying the following:

  1. Mixdown your project to a stereo wave file for both versions
  2. Create a new project and import the two wave files onto two separate tracks
  3. Flip the polarity of one of the tracks (make sure to flip both the left and right channels)
  4. Play both tracks together

If they are indeed identical then they will completely cancel each other out and you won't hear anything when these two tracks play together. However, if you do hear something, then that means they are producing different reults and what you hear is what is different between the two versions.

Tekkerue
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  • It’s clear but I’m concerned that it might not be correct. Some summing algorithms will perform differently with different level signals, which means sending a hotter signal to the stereo master channel before limiting might sound better or worse. Also different limiters may respond differently. Certainly in the analog domain gain staging is critical. It’s still important in the digital domain but in different ways. – Todd Wilcox Jan 26 '18 at 06:03
  • but limiter only add gain to my overall mix. right? i mean it could be different when i use comperesor or other plugins. but limiter? i dont know. by the way, i use izotope and fab filter limiters. – dana Jan 26 '18 at 10:55
  • @dana A limiter by itself does not add gain. It reduces levels that exceed a certain limit, which is why it's called a limiter. A lot of "mastering" limiter plugins have a feature called *makeup* turned on by default. What that does is increases the overall level of the sound by the same amount as the maximum reduction that the limiter would cause. Like with Izotope Ozone, if you put the max at -1 dB and the threshold at -7 dB, the max limiting will be 6 dB, so it will automatically increase the level of the whole thing by 6 dB and then limit anything that goes above -1 dB. – Todd Wilcox Jan 26 '18 at 16:27
  • @Todd Wilcox, I just varified this myself in Samplitude. I did the comparison within one project using submix tracks instead of mixing down to wave files (but same effect as above). I duplicated 4 tracks and sent each group to different submix tracks. Each track for 1st group was turned down -20dB and the submix limiter (sMax11 in Samplitude) added 20dB. The 2nd group of tracks was turned down -10dB and the submix limiter added 10dB. I flipped the phase of one of the submix tracks and played them both together. The result did not register on the volume meter, which varifies they are identical. – Tekkerue Jan 26 '18 at 17:28
  • There might be limiters and DAWs where it is not true, that's all I'm saying. Certainly if one uses one of those virtual summing amps that recreates a classic console, I would expect it to be definitely not true. The whole point of those virtual summing amps is that they won't have 100% linear response over the whole range of input. – Todd Wilcox Jan 26 '18 at 17:29
  • yes thats totally true. the thing that limiter do is limit the loud part, increase the down part and then add makeout gain to increase the overall sound. the thing that i dont understand is how is this thing affect my final result. because both of the time it is doing the same thing. unless you tell me that the limiter will work differently when it receive low or high input(something like adding distortion or ... coz i know that some compresors like CLA would do that , beside compressing). – dana Jan 26 '18 at 17:42
  • If you are using something else that is designed to affect the sound in a specific way while summing then yes, results could certainly be different at different volume levels. However, different DAWs shouldn't give different results on this. There have been numerous null tests done comparing DAWs from ProTools to Reaper and everything in between and I'm not aware of any major DAW that has failed the test. But again, the best way to know if your limiter or DAW is producing different results at different volumes is to do the null test. That will tell you 100% for sure if there is any difference. – Tekkerue Jan 26 '18 at 18:03
  • thank you both for your answers. today i ran a test to see what will happen. as i said i use cubase and izotope limiter. i used a kick as my subject, first i used a little gain on my limiter and acheived -3 db on my rms. then used more gain on my limiter and again reached -3 db on my rms(with my kick track fader, down). then i phase reversed on of them . and when i played both of them together, there were lot if phase cancallation but not compeletly !!! still i could hear a lot of sound. so in my opinion the limiter was doing more than just adding gain. even when i looked closer to the shape.. – dana Jan 27 '18 at 14:28
  • of sound, the two new sounds, had a little differences. so i just wanted to say that for a record and anyone who read this question. if any one else have any other idea, i am all ears. thank u again – dana Jan 27 '18 at 14:30
  • i ran the test with fabfilter pro l and the result was the same as i mentioned above( when i did that with fabfilter , there were more phase cancallation ) – dana Jan 27 '18 at 14:49
  • If you are using the rms meter to guage when they are the same volume then it's possible that the levels may not be *precisely* the same. In the test that I did above if I change the limiter on group 2 to 10.01dB instead of 10.00dB then then the volume meter starts showing a difference. Because instead of adding back exactly 10dB that I reduced on the tracks I added back 10.01dB which will caused a 0.01dB difference between them and they did not null completely. When setting the controls on your limiter look at the values make sure that the math works out the same for both versions. – Tekkerue Jan 27 '18 at 15:10
  • Also, if the limiter allows fo it, make sure to type in the values with the keyboard instead of moving the controls with the mouse. This way you can make sure it is exactly what you want and doesn't end up at 10.03dB when you want to set it to 10dB. Under normal circumstances this kind of nit picking isn't really necessary, but when you are trying to get a null test everything has to be spot on because even 0.01dB difference is enough to ruin it. – Tekkerue Jan 27 '18 at 15:22
  • so what measurement you suggest? i typed the values with keyboard and i made sure to have the exacte same values on my output rms. but maybe you are right. so what should i do to make sure that they both have the same loudness?thanks – dana Jan 27 '18 at 19:55
  • Let us [continue this discussion in chat](http://chat.stackexchange.com/rooms/72333/discussion-between-tekkerue-and-dana). – Tekkerue Jan 27 '18 at 22:09
  • again i mono my kick , and used vu meter for loudness. when i phase reverse the second track, they phase cancalled each other perfectly, but when i added delay reverb and distoration to main track and repeat the process, it was the same as i said before and there was still hearable sound. so i think that maybe its different between mono and stereo when it come to changes that more gain on limiter could do to single track – dana Jan 28 '18 at 13:22
  • Are you saying that the kick track at two different volumes and using only the limiter to match the volume both cancel out? If so, then it is not the limiter that is causing the differences. :) Stereo effects (like reverb, stereo delays, chorus, etc.) can have randomized parameters in the algorithm which will cause you to never get the same results twice. But if you can get it to null using only volume and the limiter, then the diferences you hear are from the other effects you are adding and not from the limiter itself. – Tekkerue Jan 28 '18 at 16:51
  • yes you are right . i shouldnt use effects like reverb. my bad. so again i repeated the process. its interesting. whenever i use mono kick, the results are the same as you said. but when i use stereo kick, its not totall phase cancalation. i checked carefully both left and right channels for sound matching. so i wonder is it because of some tiny volume differences that my analyzers couldnt show or is it because of stereo character of my sound? – dana Jan 28 '18 at 20:54
  • Stereo vs mono in itself shouldn't cause any difference. I did my test with stereo files and they nulled out completely, but I didn't put any effects on the tracks. How are you achieving your stereo kick sound? Are you using any other effects for this? – Tekkerue Jan 29 '18 at 23:27
  • no i learned my lesson ;) i didnt use any effect. i imported an stereo kick, did the process, there was a little sound remaining. then i mono my first imported kick, did the process exactely the same , and this time the sound was completely vanished!!! – dana Jan 30 '18 at 12:57
  • Which limiter are you using the iZotope or Fab Filter?...or did both give the same result? I'm not sure the iZotope limiter but the Fab Filter limiter can enable/disable stereo linking, so maybe try swapping that to see if anything changes. – Tekkerue Jan 31 '18 at 04:11
  • hello again. sorry for my late response. i stereo linked my limiter( both on fabfilter and izotope) and you are totally right. it phased out my sound completely. but there is something that still bothering me. there are some of mixers that saying that its best to use two limiters on the master bus , i wonder if its the same result and its only adding gain to whole mix, whats the point of adding two limiters??? – dana Feb 03 '18 at 18:33
  • Here are a couple explanations for using multiple limiters: https://www.sweetwater.com/insync/multiple-limiters/ and http://www.musicradar.com/tuition/tech/13-pro-mastering-tips-523509 (the section called "Use multiple limiters") – Tekkerue Feb 04 '18 at 08:22