# Gain Staging for recording and mixing



## rocksure (Mar 4, 2012)

How loud to record, how hot a signal should you record with? How much headroom do you need? I have seen these kind of topics coming up on various forums and blogs. A few years ago I used to record everything pretty hot. As long as the signal didn't clip I would try and get up close to zero when recording. Mixing was a juggling act trying to get everything to fit into the master buss without distorting. Trying to get clean, clear transparent mixes was a real mission. Then I discovered sensible gain staging and dropped my recording levels. Mixing became a whole lot easier. So anyway, I wrote a short tutorial on the subject, which some of you may find helpful, or maybe it will spark some further discussion. I am posting a link to it here:
audio-gain-staging


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## wgmontgomery (Jun 9, 2011)

Thanks; lets hope that some professional engineers start to understand that louder isn't always better! :wits-end:

You have to have "quiet" and "loud" to have dynamic range; if everything is recorded at -4db to 0 db it doesn't leave much room for dynamics. :hide:


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## rocksure (Mar 4, 2012)

Yes dynamics are great to have in my opinion. I like to mix leaving room for them. But even if you don't want dynamics, and want a very squashed sound, and lets say that you have 36 tracks of audio all recorded close to 0, and you have to mix them down to stereo, you leave yourself no headroom to work with.


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## planetnine (Mar 3, 2009)

With analogue recording, we used to aim for 0VU or thereabouts, and that usually had a level of +4dBu, or about 18dB below the channel's clipping point. _Now I know we used to record to tape and you had to hit it at a certain level to get a reasonable Signal to Noise Ratio (SNR), and I also know that you wouldn't get far into the next 12dB with the tape and heads, but when it saturated it did so reasonably musically._

When we started recording digitally, saturation wasn't an option (that last bit just isn't spongey enough), so we had to leave some good headroom. 18dB seemed like a good idea again, but early ADC were not (esp in hindsight) that nice a lower levels they were only 16-bit too at the start, and the quieter stuff soon sounded "not right" after some processing, so we learned to get the levels within 12 or even 6dB of DFS.

This seems to have stuck as a mind set. We now have fantastic converters and 24-bit resolution, but still people walk that tightrope between hot and bust -hey fellas, you don't need to anymore. We give ourselves 18dB of headroom on consoles between +4dBu and +22dBu, so do it for digital! Aim it for -18dB and you'll just not have to think about encroaching levels and you can just mix.

Professional DACs will give tyou about +4dBu for your -18dB and that is a good analogue level. The cheaper audio gear starts to sound strained and brittle in those top few dB anyway, so it is good practice.

I location record at +4dBu, -18dBDFS (digital). I try to mix at -18dB DFS. I don't ram those limiters until I render monitor mixes or master the recording (and then I bung a mastering limiter on the master just for that purpose and then bypass it agin afterwards).

I think many people struggle with this concept because they don't have their monitors set up to deal with it. Trying to deal with -18dB and full levels without a monitor controller is difficult or even dicey to say the least.


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## rocksure (Mar 4, 2012)

planetnine said:


> I think many people struggle with this concept because they don't have their monitors set up to deal with it. Trying to deal with -18dB and full levels without a monitor controller is difficult or even dicey to say the least.
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Yes very true. 
I have my monitors running from a mixing console, and have marked positions on faders for levels for TV mixing, general music recording, and also for full level mastering volume. I set the monitoring levels with an spl meter so I have a relatively consistent reference.


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## Syd26147 (Jul 4, 2008)

*Sound System Gain Structure* ( John Murray)
http://www.naterecording.com/gainstructure.pdf


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## elbradamontes (Jun 7, 2012)

Correct me if I'm wrong but isn't gain staging all about signal to. Noise ratio? And if you record in hot, what's wrong with simply turning down the individual tracks? So two scenarios. Rhode K2 into daw via apogee duet from a booth. Absolutely no white noise or background noise but I'm not running through a compressor. So...I keep the volume low to avoid the horrendous duet clipping. Then I simply compress and turn up the track. Two. Guitar direct in. Completely different tone and almost unusable signal if the input isn't pegged. Compress and turn down the track. That being said, immediately after reading this article I was working on a track and thought "why am I riding the red led?" so yeah I fell into the trap too.


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## rocksure (Mar 4, 2012)

elbradamontes said:


> Correct me if I'm wrong but isn't gain staging all about signal to. Noise ratio? And if you record in hot, what's wrong with simply turning down the individual tracks? So two scenarios. Rhode K2 into daw via apogee duet from a booth. Absolutely no white noise or background noise but I'm not running through a compressor. So...I keep the volume low to avoid the horrendous duet clipping. Then I simply compress and turn up the track. Two. Guitar direct in. Completely different tone and almost unusable signal if the input isn't pegged. Compress and turn down the track. That being said, immediately after reading this article I was working on a track and thought "why am I riding the red led?" so yeah I fell into the trap too.


It is unnecessary and counter productive to record anywhere near zero. Simply pulling down the individual track faders doesn't give you more headroom.

Here is a quote from the audio-gain-staging article:
"If you find that signals in your DAW have been recorded too hot for clean mixing with plenty of headroom, the use of trim plugins is the first place to go. Using one of these as your first plugin on each channel, you can adjust the level going into EQ’s, compressors and other processors. This is not the same as just pulling down the fader, because that only affects the signal level going to the master buss or summing busses. The trim plugin acts like the gain control on your preamp, whereas the fader is like the output volume control."


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## elbradamontes (Jun 7, 2012)

Ok. So I should have read this thread, specifically the referenced article, more closely. I'm mixing a demo right now that is plagued by compression woes and I haven't even put the vox in. So... I think I just got it!!! So I have a near zero vocal signal. I decide that 400-550hz needs to come out and I want to boost 5-8h maybe 5-10k cause i used a "dead" booth with shite treatment but when I do, I get some distortion. So I pull the eq gain down a notch but still run into compression distortion so I switch to opto compression which keeps some air but still causes problems at usable output levels. So I pull the knee down to near zero and the ratio down to 2 hoping to avoid the "even order harmonics" but end up having to automate the volume fader to achieve any balance. 

BUT!!!

If I had lowered the levels to say minis 4 I could have provided myself headroom not for the output stage but specifically for eq and compression? (And reverb if I might add.) and avoided these issues?

I am currently almost literally praying that the answer to this question is yes.


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## tonyvdb (Sep 5, 2007)

Are you saying that the original track you are trying to EQ has distortion (clipping) in it already? not much you can do with that other than re record it or keep the level down on it and use other tracks that are clean to cover it. "Garbage in, garbage out"


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## elbradamontes (Jun 7, 2012)

Negative good buddy. Source material is clean. I'm just not wrapping my head around this headroom we're providing ourselves. Headroom for what exactly? Let's walk backwards. Monitors driven too hard. Turn them down. Output stage of interface clipping. Turn it down. Software out mix clipping in interface. Turn it down. Master bus output stage left and right clipping. Turn it down. Master bus input stage clipping. Turn all your tracks down. Too much signal going into your reverb or eq. Aha! One, either put a compressor or limiter in the first plugin spot before all other effects or... back off zero while tracking. I'm just trying to clarify what we gain by recording at say minus 3. What exactly are we saving that headroom for? Signal processing? My eq (logic) has a little gain slider. I always place eq first in the chain. If I need to I just pull a little off the gain at that point. However...I do have a mix I'm dealing with right now that just seems too crowded no matter what I do. I'm wondering if the point here is that:

there's a marked difference in the mix between pulling the sliders down (output stage) for each track and leaving room in each track while tracking. And, 

is there a usable difference between coming in less hot and simply trimming some signal off at the beginning of the chain before processing?


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## tonyvdb (Sep 5, 2007)

I think maybe you reading into this just a little to much, lets back up here a bit and look at the so called "Loudness wars" thats become a problem in the last few years. The issue with not giving some headroom is that you end up compressing or EQing the signal weather it be a single track or the entire mix to get the mastered level to as loud as possible without clipping, Very bad in my opinion. I myself like the rise and fall of the individual interments and vocals as they were meant to be heard. By running everything as hot as possible you loose dynamics and clarity.


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## elbradamontes (Jun 7, 2012)

Ok as I read back through some of the responses and my big question I realized what everyone's talking about and what I was talking about are one and the same. Yes I was reading too much into this. I guess I still hope to find some magic bullet for my mixes.


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## planetnine (Mar 3, 2009)

In a DAW you want to leave headroom for recording because you're never sure what is coming from the microphone and what the dynamics of the source will be. You can't "look-ahead" with a vocalist in the studio 


When mixing, leaving headroom is good practice, because the act of adding (mixing) tracks together will eat into it, as may compression, EQ, time-based FX such as delay, reverb, chorus, flangers, etc. Turn the wick down to a nominal level of -18dB and you really shouldn't have to manage levels for clipping halfway through your mix.

...and it's just "what professionals do" 

Once you've mixed, and you know what your levels are across the material, song, track, etc, then mastering is where you go for "normalising" up to -0.3dB DFS or whatever. I rarely get away without using a brick-wall limiter for this these days.

Headroom isn't really the riight word to be using when we move onto the subject of loudness in *mastering*; there just _won't be any_ (although I prefer to limit to -0.2 or -0.3 dB FSD) -that's more a case of mangling the peaks and transients as transparently as possible (damage limitation), to get the highest RMS value possible.

Given free reign, I'll work to Mr Katz's -14 or -12, but clients are so paranoid that someone will think their track is lacking somehow, that they will spoil the mix (yes we're talking distortion and really ugly stuff here) rather than have it sound quiet in a CD player (and then have to submit a different, quieter, master to the radio station to survive the on-air processing and end up sounding the same level as everything else!)

Another subject entirely, which I'll happily chuck my 2p in here or in another thread if someone wants to discuss it, but not really related to gain-staging in a DAW for recording or mixing 


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## Prodba (Oct 12, 2010)

Indeed, proper gainstructure/headroom has not much to do with loudness(wars) or substractive vs additive EQ, like is also sometimes claimed.

When you look at the specs of your audio equipment (console, DAW) you might see that while may it operates at +4dBU, the maximum output is +26dBU. This is a headroom of 22dB.
On a analogue system we'd calibrate our meters so that when it hits "0" on the meters, it actually outputs +4dBU, leaving us that 22dB headroom. 
On digital meters we'd have to aim at -22dBFS to maintain 22dB of headroom. 
So, when on my analogue console/PPM I'm hitting "0", I'll be at -22dBFS on my converters.

Now, what is this headroom good for?
The answer is that a signal consists of the 'main body' and its transients. 
If you look at the visualisation of for example a drum hit in your DAW, you'd see a fish-like form with a lot of long thin spikes coming out of it.
This main body (fish-like form) is what gets detected by the meters, while the transients (spikes) are too fast for the meters, let alone the human eye, to catch.
These transients, which are important in defining the character of a sound and, even though we might not detect them with our eyes, will start causing distortion in our audio system when getting close to the clipping point, can get up to around 20dB above the 'main body' of the signal.

So in short, headroom is necessary to accomodate the transients which may be +20dB above our nominal operating level. 


Headroom and subractive EQ:
I constantly hear people say that subtractive EQ is better than boosting, because it will save or give you more headroom.
Well, aside of the apparent merits of subtractive EQ, if you practice proper gainstaging this wouldn't be the case.
GAINSTAGING means that you optimize your GAIN at every STAGE of the process (when recording/mixing).
So, you start by setting your gain at the level that you find appropriate and try to mainain that level until the end of the trajectory.
If you boost some EQ along the way, you ideally would go back and turn down the gain accordingly and if you cut, you should turn up the gain to match. 
This way the headroom will always be maintained at the same level, independent of your EQ method. 
The same idea applies at all the processing stages, through the whole audiopath.


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