Low level stems.....should I normalize?

John
Are you mixing or what? Are the wave files in 24 bit or greater? What sort of music is it? And what are the instruments? Has any FX been added? What is the RMS dB value?
 
I would do the processing that you think is needed and go from there. I would only normalize if that was the only way to get the final levels I wanted. 
 
 

mike_mccue
The first question will be: What bit depth did he send you?
 
2nd: How many stems are you going to sum?
 
3rd: Have you tried summing all the sends to see how the levels stack up to see if you really need to normalize them before mixing?

John
I must be blocked. LOL

gswitz
There are a couple of useful tricks for working with low levels
- Gain nob - seems obvious but sometimes people forget. It works great. Can't be automated. Pretty much the same as normalizeing in a lot of ways.
- when in track view and drop down is set to 'Clips' on the track header, you can click in the gray divider and drag up and down to increase the size of the wave form so you can see the wave form better for quiet parts of the track
- Normalize... Normalizing to a particular level for a particular tune is a bit like setting the gain in a way that sticks. In other words, say you have a recording of 20 songs in a single project and each song needs separate gain settings. Instead of using the gain nob, you can normalize the audio and thereby control the gain into the fx sends for each song in a way that is remembered over time. If you use the gain nob on one tune, then alter it for the next tune, then go back to the first, you will need to reset the gain nob on the first tune. Can you remember where it was set? If you use normalization, you will not need to reset when you return to an earlier tune.

John
I must be blocked. LOL

mike_mccue
1) 24bit: Good news. There should still be lots of useful data in the files so turning up the level will probably not hurt the quality in a noticeable way.
 
2) 18-20 tracks: Good news. If it was only 4 or 5 tracks it may not have enough energy to sum to a useful level without having to get aggressive with a level boost.
 
3) With everything at unity gain everything does sound fine: Good news. With 18-20 tracks summed at unity it probably peaks pretty close to *insertmagicnumber*dBFS and that means that just about any way you adjust the levels will work out ok.
 
Where I was going with my questions was in preparation to explain that if you "normalize" to some louder level you'll probably end up turning stuff down instead of turning stuff up and that you might find that it is just as easy to simply turn up what you need to turn up. If you did find that you were turning stuff down after "normalizing" to some high level then some might point out that you can lose a little bit of sound quality. With 18-20 tracks in the mix it is probably not something anyone could actually notice with their ears.
 
I think Geoff explained your options very well. :-)
 
My opinion is just mix it. Use the trim and level knobs like they are supposed to be used, and don't forget that you have clip levels available as well.
 
best regards,
mike

Guitarhacker
keep in mind, you do not need to normalize to 100%.   You can always select a level less than the 100% normalize.
 
I would only normalize a track if there were no other ways to get it to set in the mix properly.
 
Instead of looking at the wave...listen to it. Now ask yourself if it sounds OK or is it in fact much too low to work with in the mix.  If it is simply too low (bad recording job or whatever) try normalizing up but not to the 100% level.  More than one time, a weak looking wave track sounded just fine in the mix. Depends a lot on the instrument and the genre. If it works with that low level weak looking wave, don't normalize it just to be normalizing it. You accomplish nothing. If you normalize it up, and then have to pull the faders down to compensate..... what have you accomplished?
 
Remember that normalizing will also raise the noise levels as well as the music.   Giving the wave a small 25% bump up above it's current levels may be more than enough to do the job.
 
My goal in normalizing is as described above and the evidence to me that I did it right is that my faders are in the nominal range from -0 to -10 or so...... if I have to pull them down further, I probably normalized too much.
 
If I have to go above -0, I need to have another look at that track and figure out why I'm needing to run that high.
 
but that's just me and how I do it.