You are here

Mastering: when to raise the audio level?

All about the tools and techniques involved in capturing sound, in the studio or on location.

Mastering: when to raise the audio level?

Postby manwilde » Tue May 26, 2020 7:53 pm

Hello, guys. I am a long time SOS forums reader, and I´ve learned A LOT from all of you. I think what you do, and the way you do it, is just magnificent in every sense. Now bear with me if the answer to my following question is scattered somewhere in the forums, but I´ve not found a precise answer: once you record with sensible levels, averaging -18dB and trying not to peak your master buss over -10 or so... what do you do to raise the volume to mastering levels?. Do you normalise your clips and then start mixing, or rather mix as it is and then pump up the volume on your master channel with plugins?. And if so, how?. What´s the best practice not to stress the converters?. I´m not talking about loudness wars here, just getting to the -14db LUFS ballpark when self-mastering your work.
Thank you very much in advance for you help!
manwilde
Poster
Posts: 49
Joined: Mon May 07, 2018 3:57 pm

Re: Mastering: when to raise the audio level?

Postby blinddrew » Tue May 26, 2020 8:35 pm

Lots of ways to skin a cat here, if you're happy with the general loudness of your mix and all you want to do is get the final volume up a couple of dB then you might as well just stick a gain plug in on the end of the master bus and knock it up a few dB (aiming for -1 for WAVs but about -3 for MP3s).
Indeed, if you send a great mix to a mastering engineer that might be all they do.
But there's generally a bit more to it than that, which we're not really going to cover on a thread like this!
I went on a course run by the guys who wrote this book: https://blackwells.co.uk/bookshop/produ ... ZEQAvD_BwE and they took us through a logical process that covers a number of bases. I'd recommend the book as it walks you through a range of tools and techniques as well as giving you a template process to experiment with.
User avatar
blinddrew
Jedi Poster
Posts: 11250
Joined: Sun Jul 05, 2015 12:00 am
Location: York
Ignore the post count, I have no idea what I'm doing...

Re: Mastering: when to raise the audio level?

Postby Hugh Robjohns » Tue May 26, 2020 8:36 pm

As always, there are as many techniques as people you ask...

But I prefer to concentrate purely on crafting the best possible mix, maintaining a reasonable headroom margin. And once I'm happy with the mix I can then focus on mastering for whatever format requirements might be needed.

That said, if you get your monitoring reference level right, and have the right metering tools, it's quite possible to hit the right target loudness pretty much at the mix stage, and so not necessarily need to go through a separate mastering stage at all. To help with that I would normally mix into a bus compressor, and run a good peak limiter over the top to take care of any wayward transients.
User avatar
Hugh Robjohns
Moderator
Posts: 28326
Joined: Fri Jul 25, 2003 12:00 am
Location: Worcestershire, UK
Technical Editor, Sound On Sound

Re: Mastering: when to raise the audio level?

Postby James Perrett » Tue May 26, 2020 9:24 pm

If I'm mixing I won't really think about mastering. I will only think about mastering once I know what the release formats are going to be and then produce separate vinyl/digital masters for the whole release. Where more than one song is involved in a release, such as on an EP or Album, the whole thing needs to hang together and, while LUFS measurements are a guide, they can't make up for listening to the whole thing and deciding on final levels by ear.
User avatar
James Perrett
Moderator
Posts: 9660
Joined: Mon Sep 10, 2001 12:00 am
Location: The wilds of Hampshire
JRP Music - Audio Mastering and Restoration. JRP Music Facebook Page

Re: Mastering: when to raise the audio level?

Postby Mike McLoone » Wed May 27, 2020 8:01 am

manwilde wrote: Do you normalise your clips and then start mixing, or rather mix as it is and then pump up the volume on your master channel with plugins?. And if so, how?. What´s the best practice not to stress the converters?

If the audio track is a bounce of a plugin, the level in the clip is usually going to be high enough, I'll leave it alone. If it's a recorded instrument, I might adjust the level of the clip if it's too low. I would not normalize to -1dBFS specifically, but just get something in the -30dBFS to -1dBFS range as a ball-park.

The simple advice is to bring the bass & kick channel faders up until you get around -20dBFS on the master bus. This is a rough place to start the mix. You must leave the master bus fader at it's zero gain / default position. You will have to adjust your monitoring volume levels, that is to say, not in the DAW but using monitoring controls on your audio interface or hardware mixer, to listen at a comfortable level.

Once all the elements have their faders up, you should be able to play through the mix without clipping the master bus. If not, select all the channel faders at once and drag them down a few dB to create more headroom. Careful not to drag down any bus or master bus faders in the process.

Once this mix is bounced to disk, there will be a certain amount of headroom, from the loudest peak to 0dBFS. It does not matter how much headroom there is, just as long as there is some and you have not clipped the master bus.

Open a new session in the DAW and bring the bounced stereo pre-master in. Now, using a combination of gain plugins, compressors, EQ, multi-band compressors and final limiters, you will bring the levels up to the required delivery target, -14LUFS (Spotify/YouTube) / -12 LUFS / -0.5dBFS (for CD mastering) etc. It's using simple gain plugins one can bring the level up, and it's the final limiter which is used to prevent clipping, the drive will be adjusted in the limiter to hit the -14LUFS target.

The other compressors, EQs and multi-band may be adjusted so they are not adding to the peak levels, and can be turned on and off without the level being raised or lowered significantly.

One trick is, if you are working on a style which relies on heavy amounts of mastering compression, say dance music, you can apply a mastering compressor/limiter on your master bus during mixing. This is only to get a feel for how it will sound after mastering. Make sure to disable any such plugins before bouncing the stereo pre-master. If you really like the sound of that compressor/limiter you had during mixing, then you can save the preset and then load it into the same mastering compressor/limiter during the mastering session.

The reasons for separating the mix and master processes are many. Giving your ears a break between mixing and mastering is one reason. Being able to give the pre-masters to someone else to master is another. Yet another, you might have a bunch of tracks for an album, and you will want to master these in one mastering session, so that they fit together and sound similar. If you had applied the mastering limiter and other processors to the mix as you were doing it, you may not be able to go back on those decisions.

You cannot "stress the converters". Line inputs have protection diodes to protect the A/D, line outputs don't care how high you drive them. Mic inputs or instrument inputs, OK, these have more gain and if you are feeding in a line level signal, start low and raise the level to avoid damaging the pre-amp.

Just be careful of your ears and don't monitor at too high volumes for too long. These are the converters which can be stressed! ;)

Best,
Mike
Mike McLoone
Regular
Posts: 106
Joined: Thu Apr 24, 2003 12:00 am
"It's all gone quiet." said Rhubarb "Not nearly quiet enough." said John Cage

Re: Mastering: when to raise the audio level?

Postby manwilde » Wed May 27, 2020 9:29 am

Thanks so much everyone for your detailed answers. My problem usually is that I feel I´m too low when I reach the master channel for any compressor to react. Then it´s either lowering the thresold to something like -20 for it to start doing 0.5-1dB worth of gain reduction, or strapping some clean plug-in (usually TDR Nova) and raise the volume as much as 10dB before hitting the compressor (if I like what it´s doing) or just the final peak limiter.
I normally mix on headphones (AKG 701) and use monitors just to check pannings, reverbs and vocals/instruments balance. I have Totalmix templates taking care of monitoring levels depending on whether I´m tracking, mixing or mastering, but by no ways are these based upon any scientific measurement, just trying not to blow my ears and balancing against reference tracks by ear instead. Hugh, is it really crucial to check my levels against sine waves and the whole thing?. I´ve read quite a few times about Bob Katz´s K-System and it seems a bit convoluted to my level of work, but I don´t wanna miss out on something important just out of laziness.
I used to carry different sessions for mixing and mastering, but now I do everything on the same project: fisrt I mix best as I can, then I do all the pseudo-mastering with plugins on the master bus, just to find out my mix is lacking these and that. Maybe I should go back to different sessions for each task, but I find convenient the ability to tweak the mix at the moment without having to go back and forth. If I get to do too much on the master I scrap it all and remix the whole thing.
Blindrew, thanks for the call on that mastering book, looks like a good place to start improving. And thanks again to you all!
manwilde
Poster
Posts: 49
Joined: Mon May 07, 2018 3:57 pm

Re: Mastering: when to raise the audio level?

Postby CS70 » Wed May 27, 2020 11:33 am

manwilde wrote:Thanks so much everyone for your detailed answers. My problem usually is that I feel I´m too low when I reach the master channel for any compressor to react.


A lot depends on the music you mix. Drums and bass have loads of energy. It's hard to get a mix including them which doesn't peak at least around -6. A vocal+guitar mix will peak quite a bit lower.

Then it´s either lowering the thresold to something like -20 for it to start doing 0.5-1dB worth of gain reduction, or strapping some clean plug-in (usually TDR Nova) and raise the volume as much as 10dB before hitting the compressor (if I like what it´s doing) or just the final peak limiter.

In principle there's nothing wrong with it (I'd rather use a gain plugin tough, the free BlueCat Gain is a favorite here), but it's an indication that something might be off in your gain staging as you'll obviously increase noise as well.

I used to carry different sessions for mixing and mastering, but now I do everything on the same project: fisrt I mix best as I can, then I do all the pseudo-mastering with plugins on the master bus, just to find out my mix is lacking these and that. Maybe I should go back to different sessions for each task, but I find convenient the ability to tweak the mix at the moment without having to go back and forth. If I get to do too much on the master I scrap it all and remix the whole thing.

I tend to "pseudomaster" on the master bus only for demo stuff - usually nothing more than a limiter so the band guys don't have to turn up the volume.

While the ability to tweak is useful, the fact that it's made harder by two separate projects is a bit the point - when you mix, concentrate on mix. Mastering is a different step with different goals (check out my blog post here if you like).

What you end up doing by having stuff on the master bus which changes the sound is to mix in a different form. Not a problem by itself if you are very disciplined but you risk to make the job harder for the actual mastering step. But of course if you don't have an actual mastering step afterwards, it's just fine :D
User avatar
CS70
Jedi Poster
Posts: 6062
Joined: Mon Nov 26, 2012 1:00 am
Location: Oslo, Norway
Silver Spoon - Check out our latest video and the FB page

Re: Mastering: when to raise the audio level?

Postby James Perrett » Wed May 27, 2020 12:23 pm

manwilde wrote:My problem usually is that I feel I´m too low when I reach the master channel for any compressor to react. Then it´s either lowering the thresold to something like -20 for it to start doing 0.5-1dB worth of gain reduction, or strapping some clean plug-in (usually TDR Nova) and raise the volume as much as 10dB before hitting the compressor (if I like what it´s doing) or just the final peak limiter.

My compressor thresholds are nearly always between -30dBFS and -20dBFS which is where they should be if you have sensible levels. Don't go raising the level because there's no need.
User avatar
James Perrett
Moderator
Posts: 9660
Joined: Mon Sep 10, 2001 12:00 am
Location: The wilds of Hampshire
JRP Music - Audio Mastering and Restoration. JRP Music Facebook Page

Re: Mastering: when to raise the audio level?

Postby RichardT » Wed May 27, 2020 1:06 pm

There are some great answers here.

The only thing I ‘d add is, if you’re self mastering multiple tracks, it can be helpful to import the final mixes for all the tracks at once into a single DAW session or project, each one into a separate track and aligned start to finish. Or you can use something like Wavelab for this.

That way you can apply separate mastering processing (EQ, compression, gain, limiting) to each track, set the gaps between tracks and listen to whole thing from start to end.
RichardT
Regular
Posts: 272
Joined: Fri Aug 13, 2004 12:00 am
Location: London UK

Re: Mastering: when to raise the audio level?

Postby manwilde » Wed May 27, 2020 1:15 pm

Thank you again. To clarify a bit more, what I do is mostly in the pop-rock genre, from soft, whispering ballads to power pop with fast guitars. Most of the stuff at home, EZDrummer and a Fender Fuse modelling guitar amp recorded through the line out into the interface. Bass is DI, some MIDI keys and a mic for vocals.
I think the key for me here is monitoring gain stagin. I record as I´ve unadvertenly been told by you in lots of other posts, with conservative levels. But, for instance, to record vocals and have a good balance in the cans the DAW return volume in Totalmix is around -18dB, mic fader at 0dB and the mic input peaking at around -10db mostly. Isn´t it way too much of a difference?. And when inserting a saturation plugin (but not only) in mix time it seems like it´s doing nothing unless you raise the clip gain +6dB or so, which I tend to do, also to keep my mixer faders closer to the 0dB area so I have finer control on slight volume changes.
Besides, I try not to change the volume of a track when I insert any effect to prevent my ears from being fooled, thinking that louder sounds better. So that´s why the main overall volume lifting is left to the master channel...
So how can I, as Hugh stated earlier, get more level into my mixbuss prior to any processing there?. Is it just a matter of well implemented, selective compression on the tracks?. Or am I being too fussy and should just get over it, mix raising my monitoring levels and then master the song aside?
Thank you!
manwilde
Poster
Posts: 49
Joined: Mon May 07, 2018 3:57 pm

Re: Mastering: when to raise the audio level?

Postby manwilde » Wed May 27, 2020 1:21 pm

Thanks, Richard. I seldom master many songs at once, unless it´s an outside job, which I sometimes do. For my stuff, I insert Melda´s Loudness Analyzer as the last plugin on the master track set to a target of -14 LUFS, EBU+18, and let that and my ears tell me whether I am too low or not... the results, loudness wise, come sometimes fast and easy, though it takes more work more often than not. It depends a lot on the kind of song, of course...
manwilde
Poster
Posts: 49
Joined: Mon May 07, 2018 3:57 pm

Re: Mastering: when to raise the audio level?

Postby James Perrett » Wed May 27, 2020 1:24 pm

manwilde wrote:So who can I, as Hugh stated earlier, get more level into my mixbuss prior to any processing there?
...
Or am I being too fussy and should just get over it, mix raising my monitoring levels and then master the song aside?

I think you've just answered your own question. There's no need to increase your levels into your mix bus. If you have a plug-in that requires elevated levels then boost the level going into the plug-in and then reduce the level again on the output.

Treat the mastering as something totally separate.
User avatar
James Perrett
Moderator
Posts: 9660
Joined: Mon Sep 10, 2001 12:00 am
Location: The wilds of Hampshire
JRP Music - Audio Mastering and Restoration. JRP Music Facebook Page

Re: Mastering: when to raise the audio level?

Postby RichardT » Wed May 27, 2020 1:36 pm

As James says, these days the overall level of the mix bus isn’t too critical as long as you export your mixes at 24 bits. That gives you plenty of headroom. You can adjust the gain in the mastering process to give you the right loudness and peak levels.
RichardT
Regular
Posts: 272
Joined: Fri Aug 13, 2004 12:00 am
Location: London UK

Re: Mastering: when to raise the audio level?

Postby CS70 » Wed May 27, 2020 3:23 pm

manwilde wrote:I think the key for me here is monitoring gain stagin. I record as I´ve unadvertenly been told by you in lots of other posts, with conservative levels. But, for instance, to record vocals and have a good balance in the cans the DAW return volume in Totalmix is around -18dB, mic fader at 0dB and the mic input peaking at around -10db mostly. Isn´t it way too much of a difference?

Yes, I can understand well and perhaps the issue may be less familiar to people who do not record their own vocals.

-18/-12dB at 24 bit FS are recording levels. As monitoring] levels, you can have as much more as you want and your headphones (and ears) allow. The problem is that when you record alone most often you're using direct monitoring from the interface, so your headphone outs return exactly the level you set for the recording - because it returns whatever signal the inputs are seeing right after the preamp.

The solution is simple: either the interface has an additional gain stage (i.e. volume knob) for the headphones, or you use an headphone amp (often on a monitor controller).

You set your gain so the recording levels are what you want, and then the separate gain for headphones so that you hear whatever level you want.

And when inserting a saturation plugin (but not only) in mix time it seems like it´s doing nothing unless you raise the clip gain +6dB or so, which I tend to do, also to keep my mixer faders closer to the 0dB area so I have finer control on slight volume changes.

Normally these plugins (like many compressors) have an input and output knob and it's perfectly ok to turn them as much up and down as needed.. that's how you drive a preamp, for example - you crank the gain but then use the output stage to bring back the (distorted) signal to a level which is reasonable for the circuitry downstream. If the plug you use does not have such knobs, simply place a gain plugin before and after (or change distortion plugin :)).

Besides, I try not to change the volume of a track when I insert any effect to prevent my ears from being fooled, thinking that louder sounds better. So that´s why the main overall volume lifting is left to the master channel...

That's exactly how you should do it, and I wish I was more disciplined myself, especially when part of the mixing happens late at night.. :D

The thing is that when you have a bunch of tracks, the main bus is the sum of these.. so I do not understand how you can have many tracks at -18 average and not getting a much higher value on the mains..

Unless you're reducing bus levels as well?

Keep in mind that buses are summing channels, so their levels are naturally bound to be higher than an individual recorded track. A drum bus for example will naturally average around -15 or -12 dBFS - which is because drums are *loud* and made by many individual instruments.

So for example when I instantiate EZDrummer to make a demo, the first thing I do is bring down the channel gain in the DAW so that it stays around -12 with the fader at 0 (all synths I've seen for some mysterious reason are set to peak near 0 dBFS which is crazy). That's because EZDrummer, even if it appears as a track on the DAW, is really a bus - i.e. a collection of individual channels summed together (that's why you have a "mixer" in it).
User avatar
CS70
Jedi Poster
Posts: 6062
Joined: Mon Nov 26, 2012 1:00 am
Location: Oslo, Norway
Silver Spoon - Check out our latest video and the FB page

Re: Mastering: when to raise the audio level?

Postby manwilde » Wed May 27, 2020 7:32 pm

@James: Yes, I will do that from now on, thank you so much for directing me to the wise and easiest way (and thanks to everybody else, as well).

@CS70: Sorry for not clarifying, I do use a headphone amp and play with combinations of fixed volumes both on Totalmix snapshots and that amp depending on what I´m doing at the moment, and also depending on the cans I´m using, tracking or mixing. I also have templates on Reaper for EZDrummer routings, so each plugin channel has its own track and all goes to a buss peaking around -10dB. I´ve recently discovered that with drum plugins, just as with real drummers, you have a much better sound if you lower a tad the velocity (or hit a bit softer).

I´m also fussing around with creating cue busses within Reaper to send to the headphone mix, so I can selectively reinforce certain track´s volumes if I need to...

Now, back to work for better mixes. I really appreciate your comments and help!.
manwilde
Poster
Posts: 49
Joined: Mon May 07, 2018 3:57 pm