Adaptive Limiter - how do I handle volume boost

[craigr68]

I've been experimenting with the Adaptive Limiter.  I insert it into the master track, typically set ceiling to -1.0 and threshold around -10.  That boosts the signal dramatically.  So to compensate I cut the gain down on the master track about -6db or whatever it takes to get a reasonable and similar volume.  This works, but is that the best practice?  How are you supposed to compensate for this dramatic boost in volume?  

I've also tried setting the Match Input Loudness (ear icon thing) on instead of cutting the Master track gain.  It sort of works, except when I do that, it seems to start out with a quick volume burst (1 or 2 sec) until the limiter kicks in.  How do I avoid this happening?   

[57Gregy]

I don't know anything about the AL, but is your project starting at measure 1?

[craigr68]

Yes, it starts with one measure of 4 metronome clicks, at measure 2 midi tracks (Addictive Drums, Modo Bass, various VST synths) start to play.

[Sidney Earl Goodroe]

Hi, I had the privilege of having the Bakers use a quote from me in the marketing ad for Adaptive Limiter! This by no means makes me an expert on mastering whatsoever.

I can only tell you my experience with AL and hope it helps.

I try to set my master bus so it peaks around -6. Then turn on AL. The next step I have found to be invaluable!!!

For CD purposes, I heard and read that the limiter output should be set for -0.3!!  It seems that some older CD players will start to overdrive if you don't leave that little extra headroom. I know that a lot of you are saying horse hockey to this but I and many of my clients and tech guys tried it and there is a discernible difference. This also seems to help with MP3 conversion as well.

For WAV digital downloads you can get away with the output at -0.1. But, as you have found, the master bus sounds better at -6 before hitting the limiter.

As I said before, everyone has their workflow. This works for me and I master album releases for pro studios all the time.

Hope this helps. Good luck!

[craigr68]

Thanks for the input.  Hmmm, I see the manual says to allow -6 db headroom, which sounds like you're doing.  I'd like to know if you have a typical AL threshold.  I assume you were referring to ceiling when you said you set limiter output to -0.3.  I find if I have threshold at -10, ceiling at -1.0, that having -6db headroom still isn't enough - AL still boosts the volume too much.  So that's when I bring down the gain for Master track to compensate.

From manual:

When recording, allow at least -6 dBFS headroom (set maximum peak to -6 dBFS).

[John]

Ok I think you are looking at the AL as a maximizer and not a limiter. -1dB for the cutoff is too high.  To me a limiter is to prevent audio from exceeding a set dB. Unless its a true brickwall limiter and even then you can still have inter sample clipping if you push it hard.   

I would start reading about Loudness Unites and LUFS.   

[Sidney Earl Goodroe]

Setting the threshold is a variable. Depending on the audio coming in determines what the setting should be. Different types of music require different settings. It is no crime to back the threshold down!!! If you notice, some of the presets are based around -4! That is a good starting point. My target area I pay attention to is the master bus output level meter. Most hard rock, hip hop, etc, my levels there are usually bouncing around -3 or 4 and the peak at -0.3. Music that is very dynamic is usually around -6 to -0.3. Those seem to be the industry sweet spots unless you are wanting to compete in the dreaded loudness war. That is a whole different argument!

[David Baay]

On 8/17/2019 at 7:34 PM, craigr68 said:

I insert it into the master track, typically set ceiling to -1.0 and threshold around -10.

I've always thought the way 'Threshold' controls typically work is counter-intuitive, and not usually helped by the way the functionality is described.  A simple way to think about it is that the Threshold is simply an input gain control, and by lowering it, you're amplifying the signal until the peaks start to run into the Ceiling.  So by setting the threshold to -10dB, you're essentially boosting the whole signal by 10dB right off the bat.

Here's how the Adaptive Limiter's help file puts it:

"Only the signal above the Threshold is limited; all signal below the Threshold has a constant gain change that is controlled by the difference between the Threshold and Ceiling."

So if you just want to limit the peaks  without boosting,  leave the Threshold at 0, and lower the ceiling into the existing peaks. If you want a little boost (typically the goal of Limiting), start with a less aggressive threshold.

The way I typically use a limiter for a final Master is to set the Ceiling it at -0.3dB (as suggested earlier to void overs with MP3 compression or problems with D/A converters in consumer devices that behave badly at the limit), and push the Threshold down until the reduction meter shows the peaks are getting knocked down by maybe 3-5dB, and not continuously. Depending on the source material, and your loudness goals, you can push it harder, of course, but I usually just want to be able to bring the level up as high as possible without noticeably losing dynamic range or having the peaks sound 'crunchy'.

If  I were sending a mix to a mastering engineer, I might take the same approach, but set the Ceiling at -6dB, and only lower the Threshold to where the very highest loudest peaks are getting knocked down a couple of dB. 

[craigr68]

Thanks David, that was helpful.  I kind of left out that the reason I wind up with a threshold in the -10 range is because it takes that much of a threshold before I see the 3-5db reduction.  I'm wondering if that's saying I don't have my Master level or the mix high enough.  Most of the music I create is sort of light listening melodic type music like Ryan Farish - chill, electronic, or whatever that is.  But I have the same problem on rocking type music like Joe Satriani or Eric Johnson.

[Sidney Earl Goodroe]

If you're boosting that much I would say go back to your mix and start bringing tracks up so you'll hit the threshold at a lower setting.

[craigr68]

Ok, this is starting to make more sense to me.  I probably should redo my mix of all tracks to be a little hotter and more refined.  But as a quick and dirty test, I brought up the Master Gain about 4db and now I'm getting around 4db reduction when I choose Medium Adaptive preset.  So having levels too low has probably been my biggest problem all along.  I'm wondering how you monitor the levels so accurately - like where you say " -3 or 4 and the peak at -0.3".  What I'm doing is going into Console View, setting Playback Meter Options to Pre-Fader.  I set the meter range to 12db so I can observe the high region.  Then I keep an eye on the peak number adjacent to the meter.  That to me seems to work, but are there other or better ways?

Anyway, it's probably not that critical for me since I'm not doing mastering, just making backing tracks.  But I still want it to sound good.

[chuckebaby]

Its not odd at all, especially in large projects to have each individual track below 0db. In most instances where I have up to 6 guitar tracks (30 tracks total) most faders on Guitar tracks are set approx. -20db. If not, the sum eventually adds up and overloads the master bus (Set at 0db).

[John]

Chuck makes a very important point.  The master bus is summing all the tracks which adds volume. If one keeps all the tracks in a projects at or near 0dB the master bus will be in the red all the time. 

I have mentioned this before but one neat way to start mixing is pull all the faders down to infinity and move each up one at a time listening closely for balance. You may want to set a preliminary pan at this point too.  By the time all are at or near the perfect level your mix should be well on its way to sounding good. There it a lot more to it but that to me is the very first thing to do.  

BTW this is without any FX. 

[Sidney Earl Goodroe]

I always leave my master bus level slider set at 0. It never moves. I have the limiter in the FX bin but bypassed! I then start on the mix on my tracks with a target of -3 to  -6 on the master bus output meter. When the mix is close to what I want I then activate the limiter with the output on the limiter set to -0.3. Then adjust the threshold to your preference.

This is the way I have always used a limiter on the master bus. Remember to always put the limiter very last in the chain and if you use ProChannel set the fx bin to pre. This way the ProChannel FX are feeding into the FX bin thus assuring the limiter the very last processor of the mix.

Everyone works differently but this workflow has been my foundation for many, many years. Even back in the hardware days.