Super Basic Audio lingo - what's the deal with 0db, -6db and all of that

[Marc2109]

Well..I am really an old guy who is a audio and Daw newbie. There is so much I read that I just don't understand. I was hoping someone could explain a few things to me:

1. What is unity gain and why do I need it?

2. What is the significance of 0db on my fader?

3. What's the significance of -6db? I read mentions of this, but have never really seen and explanation.

I know that all of this has something to do with record and playback levels, but I don;t understand the relationship between them.

Forgive me for posting cuz I'm sure this has been asked a bunch of times. I just don't really understand what I am reading in the posts.

Thanks for the help. I'm using Sonar X2.

 

[Steenamaroo]

Hey Marc.

In analog audio there are usually several points at which you can adjust the level of the signal.
The gain knob, the eq section, the fader etc all allow you to amplify or diminish the signal level.

Unity gain suggests that a signal is neither amplified nor diminished.
What goes in is what comes out, in terms of volume anyway.

In a typical scenario, I guess 0db on a fader may be another way of saying unity.
In Protools, and I guess most Daws, the faders are set for unity by default when a track is created.

With a fader in this position, your meters are an accurate reflection of your signal level and gain settings.
Think of the fader as a volume control after your recording. If you adjust the fader, the meters won't accurately represent the level of your recording.
(This is assuming the meters are post fader; The faders are.)


I don't know what you mean by the "significance of -6db".
In relation to an analog audio fader, setting it to -6db will just turn down the audio signal.

 

[Marc2109]

Thanks so much for the explanation. That really helps. About the -6db, what I mean is I hear about recording at that level, or running a test tone recorded at that level- things like that. Why -6db, why not -8 or -10? Hope that clarifies my question a bit

 

[ecc83]

Thanks so much for the explanation. That really helps. About the -6db, what I mean is I hear about recording at that level, or running a test tone recorded at that level- things like that. Why -6db, why not -8 or -10? Hope that clarifies my question a bit

Hi Marc, I am a really old guy too but I have been doing this stuff all my life (but digital only the last 5years or so).

The -6dB thing sounds like a hangover from tape recording days? See, tape does not really have a natural limit, the harder you drive it the worse the distortion gets so they had to come up with an arbitrary "zero" level of recorded magnetic flux (32milliMaxwell per mm, in case anyone wanted to know!).
Digital does have a limit. 0dBFS indicates that you have "used up all your bits", cannot go past that.

But in practice you would never get close to 0dBFS. The standard average level you want is around -18dBFS (means Full Scale BTW) loud peaks might hit -10 and SERIOUSLY loud peaks, once in a very long time might hit -6dBFS. This assumes you are recording at 24 bits (and 44.1kHz, no point going anywhere else IMHO) . Should you be stuck with a 16bit only system you would need to average -14ish but watch those peaks. In practice -18dB and 16bits often works fine anyway.

But Hey! Us wrinkles should stick together! If you want, PM me for a bit of 1 on 1?

Dave.

 

[guitaristic]

Well..I am really an old guy who is a audio and Daw newbie. There is so much I read that I just don't understand. I was hoping someone could explain a few things to me:

1. What is unity gain and why do I need it?

2. What is the significance of 0db on my fader?

3. What's the significance of -6db? I read mentions of this, but have never really seen and explanation.

I know that all of this has something to do with record and playback levels, but I don;t understand the relationship between them.

Forgive me for posting cuz I'm sure this has been asked a bunch of times. I just don't really understand what I am reading in the posts.

Thanks for the help. I'm using Sonar X2.

Hey Marc.

In analog audio there are usually several points at which you can adjust the level of the signal.
The gain knob, the eq section, the fader etc all allow you to amplify or diminish the signal level.

Unity gain suggests that a signal is neither amplified nor diminished.
What goes in is what comes out, in terms of volume anyway.

In a typical scenario, I guess 0db on a fader may be another way of saying unity.
In Protools, and I guess most Daws, the faders are set for unity by default when a track is created.

With a fader in this position, your meters are an accurate reflection of your signal level and gain settings.
Think of the fader as a volume control after your recording. If you adjust the fader, the meters won't accurately represent the level of your recording.
(This is assuming the meters are post fader; The faders are.)


I don't know what you mean by the "significance of -6db".
In relation to an analog audio fader, setting it to -6db will just turn down the audio signal.

Another helpful tip about 0 dbFS is that it is the point (in digital audio) where sounds begin to distort and "clip"...basically don't ever go over it