Welcome to my audio-blog!
Here I'll post shootouts, some personal audio-research and more. Studio-related stuff mostly.

Monday, June 20, 2016

DAW gain-staging

From time to time newbies and more advanced users are confused and ask about gain-structure for mixing ITB (In The Box). Here I'll walk through the subject, first the short version, then looking a little deeper. I'll use Reaper as my example, but most points are valid across the board of DAWs


Mixing ITB vs mixing on an analog desk has similarities, yet there are different princippels for each. Thus, you should not confuse one with the other.

Recording/ tracking

When recording audio into your DAW, make sure you're never above 0dbfs on your AD-converters. In the 24-bit converter world, getting a too low input level is less an issue, so as long as you above let's say -35dbfs you're ok.
Practically speaking I recommend:
  • Peak-levels: Between -30 to -6dbfs
  • Rms-levels: Between -35 to -12dbfs
Aiming for -18dbfs rms is a good practice.


Reaper uses 64bit floating point as default for internal processing. This means practically unlimited headroom. So technically speaking, using plugins that handles this (like ReaEq), anywhere between -100dbfs to +100dbfs is valid.
Practically, this is not recommended for 2 reasons
  • Metering, faders -range: Metering, knobs, faders and other visual aspects are made for typically -30 to 0dbfs usage.
  • Saturation and plugin-clipping: Some plugins are made for a specific sweetspot, much like analog gear. And some will clip above a certain point.
    • -18dbfs rms is the sort of modern industry-standard
    • Some plugins have a higher sweet-spot. Variety Of Sound-plugins comes to mind
    • And some are configurable for gain of your choice.
Advice: Aim for a gain-flow around -18dbfs rms
(unless specific other needs)

Master-bus/ rendering

Although Reapers internal gain-structure may go far above 0dbfs, this is not the case when leaving the master-bus (or any hardware output). This is about:
  • DA-converters for you monitoring
  • Rendered output when mixing down your song for an wav/mp3 or similar
I'll not dwelve into mastering here, just  recommend:
  • Make sure you're levels are below -0,5dbfs peak on the master output
  • It's often wise to have a limiter as last fx on you master-channel (eg.  MGA JS Limiter). But, be aware if it's actually  limiting the audio or not. Ceiling -1,2 to -0,5dbfs.
  • You can use your limiter threshold to adjust your monitoring-levels.

Looking a little deeper

RMS vs. peak

So, what is rms dbfs vs peak dbfs?
RMS: Is an average value over a set time-frame. We often use 300ms. RMS is often similar to analog VU db.
Peak: Is an absolute value of the highest point of your wave-form.
ISP: Note that a signal may have a peak-value below 0dbfs, yet have an ISP (Inter sample peak) above 0dbfs.

Gain and faders

So, where do you set your faders?
Well, if your recorded audio is about -18dbfs rms, then starting out with faders at 0db for tracks and buses is a good idea. Then, lower the ones that needs to be quieter in the mix.
This will result in a level on masterbus that's maybe somewhere around -12dbfs rms to -6dbfs peak.
Now, adjust the threshold of your master-fx limiter to -3 to -6db, and things should be stellar.

But what if your recorded audio is everywhere but -18dbfs rms?
Well, there are different solutions:
  • Use pre-fx volume envelope/knob
  • Use a gain-plugin (anything with a volume-knob will do)
  • Use a sophisticated gain-plugin, like TBProAudio AB_LM vst
  • Normalize audio (Action > "Normalize item")
  • Or, don't care that much.

Myself I tend to go with a mix between aiming for -18dbfs rms for recording, and don't care that much when mixing. But, I'm considering changing to a -18dbfs rms mix gain workflow with pre-fx vol or something like TBProAudio AB_LM :)

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