coming back to my first post about the crest factor or dynamic range.... I guess I just felt RMS of -23 db and peaks of -6 (for a pre-mastered file) is just too much of a gap, or am I wrong?

I read in a few places your crest factor should be no more than 12 db difference.
 
Thanks for your help

As I said a crest value from 10 to 20 dB is considered normal.

aglewis723

I read in a few places your crest factor should be no more than 12 db difference.
 
Thanks for your help

Who says so and in what context, a pre mastered mix or a mastered mix because they are different. There is no limit really as to what the crest factor can be (pre msatered mix that is) , it just means you have got a lovely transient and dynamic mix going on and there is certainly nothing wrong with that.
 
The moment you master this will change anyway. Once you get the loudness levels up and start to apply compression and limiting the crest factor will change. This is where the dynamic range meter comes into its own though. You can put it over your premastered mix and get a reading and then test it after mastering. As long as you still maintain some dynamic range after mastering your mix will still sound good mastered.