Questions about volume & dB

cloudstrife · Post by **cloudstrife** » Fri Feb 29, 2008 1:41 pm

I've been writing and arranging music for years now, but I'm still a recording newbie.

I'd like to know if there's a basic rule for setting the volume of recorded tracks.
I'm never quite sure whether my song is generally too loud or to quiet. I try comparing it to professional productions, but it's still a little tough to figure out for me.

However, I heard that many modern productions are recorded in 0 dB only.
What exactly does that mean and how can they set certain parts louder or quieter than others if it's all 0 dB?

Is dB the same as audible volume, meaning that increasing dB will automatically make a track louder?

Sorry for my unknowingness.

Regards
Josh

michaellpenman · Post by **michaellpenman** » Fri Feb 29, 2008 7:33 pm

db is not the same as volume
db is intensity/power
volume is the presided level that our ears her the sound.

when they talk about 0db as a recording level this is just the measurement of the power of the recording.
on live odb is the line on the mixer where the meter defaults to.
for a recording it all depends in what you are recording. if everything is 0db in the mix it will sound crap its getting a balance between different elements

laird · Post by **laird** » Fri Feb 29, 2008 8:06 pm

Actually, dB can mean many things.
see : http://www.prorec.com/Articles/tabid/10 ... fault.aspx

you can measure the volume of passing aircraft, nearby cars, concerts, people talking and stuff in dB. More specifically, dBspl. This measures sound pressure

you can measure the "volume" of your CD player and mixer. These are electrical measurements and might be measured in dBvu

0dB of which you speak is a digital measurement and you should really say dBfs... and there's no reason to record audio files into live so that they hit 0dBfs if you record at 24bits. In fact, there are good reasons to NOT record everything so that it hits 0dBfs... mainly becuase if you go over 0dBfs you will get clipping and you can't unclip audio.

but take this test: listen to your TV. Do the commercials sound louder? They should, even though they are broadcast at the same peak dB as the TV shows.

So, yes, more dB often sounds louder, but really loudness is not the same as dB.

Affiliation · Post by **Affiliation** » Fri Feb 29, 2008 9:53 pm

as it applies to us mixing audio in digital:

Say you are listening to a sound in a track with fader set at 0db.
if you drop the fader to -6db, this is half the signal amplitude of the original sound you are now hearing.
if you drop it further to -12db, again this is half of the-6db signal so one quarter of the original.
so every 6db change is double/half nomatter where on the scale;
-70db is twice as loud as -76db for example.
this applies whether talking about rms or peaks.
minus infinity db is absolute silence.

you can bring all your mixed instruments down by 3db (from whatever they were at) and boost the master 3 db and you will hear no changes provided nothing was clipping. in which case (clipping) you have just increased dynamic range and reduced clipping:) this why we keep the master at 0db; adjust the instruments.

peaks in the audio signal can be measured in db referenced from 0db (the highest amplitude possible digitally)

rms (or power) means the amplitude of the signal if all the peaks and valleys are squashed into a flat average line; where this line would be in reference to 0db.

the trick to the loud professional productions is high rms with peaks at or near 0db while avoiding clipping or flat tops on the waveform. in the process of doing that, nomatter how good you are, dymanic range is lost (basically how many db's between rms and peaks) .
so its tricky. its an engineer job. don't make your track loud unless the track is completely finished and this is the only thing you are trying to do and in any case, always keep a backup of the quiet one which has all the dynamic range.

cheers,

michaellpenman · Post by **michaellpenman** » Sat Mar 01, 2008 8:53 am

when i was talking about DB i was being vague, i don't think it was nessuary of me to go into full detail,
by cool site you gave us.

cloudstrife · Post by **cloudstrife** » Sat Mar 01, 2008 8:43 pm

Thanks for the information!

Well, what seems a bit confusing to me (cause I'm really new to recording):
When recording guitars in Live via using Guitar Rig 3 there are two meters shown in the plugin view window.
One is "IN", the other is "OUT". And to my ears both just serve to increase or decrease the general volume.
What's the difference between them and should I set the "IN" volume to 0 dB?

So basically, from what I've understood, it doesn't matter if certain tracks are above or below 0 dB
as long as there's no clipping and the master volume doesn't exceed 0 dB, is that right?

So when the master exceeds 0 dB the volume bar turns red, doesn't it?

Where can I actually see which dB the master track is at? It is not shown when I adjust the fader.

Thanks!

Affiliation · Post by **Affiliation** » Sat Mar 01, 2008 11:15 pm

no probl.

In live you can see the actual level of any knob/fader down at the bottom left corner of the screen when you hover your mouse over it.

Yes, when the master level turns red, the audio has hit 0db and you should turn down the individual instrument tracks.

There is nothing wrong with an individual track being set above 0db; you are just boosting a quiet sound.

As far as guitar rig goes, i don't know if those in/out knobs have the ability to boost the signal or not (+dB) so cranking them all the way up may not be want you want to do.

"In" means you can control the volume coming into the rig. Set it at 0dB. Then adjust the volume of the analog sound of your guitar into your soundcard. Adjust it as loud as you can without seeing any red anywhere when everything all the way to final mix master is set at 0db.

"Out" means you can control the output of the rig after it has done whatever with your recording. (i can see transpose and tune options there and i assume it does more than that). Set that to 0 dB as well. The ableton audio track fader that the plug-in is in will be your one and only adjustment for how loud your guitar is in the final mix.

Process individual sounds while they are loud (fx and so on), attenuate them with the track fader just before mixing, and then see where you are level wise at the master track meter (always set at 0 dB).

tc

cloudstrife · Post by **cloudstrife** » Sun Mar 02, 2008 12:11 am

Thank you, Affiliation! Your info helped me out quite a bit.

Affiliation · Post by **Affiliation** » Sun Mar 02, 2008 5:09 am

just glad to help out. happy recording