Setting levels for a reference track

Meter the output of your stereo mix but set the meter so you are seeing the rms level of your mix.  It wiill average around some point down on the scale. Note that reading.
 
Drag your ref track onto a new track and set its channel fader so you get the same rms reading on the stereo mix. (Make sure you are only hearing the ref track at this point ie solo it)
 
That should get you in the ball park. The ref track is bound to be louder than your mix as it was probably mastered. So you will find the channel fader for the ref track will be lower than unity in order to get it to match your rms mix levels.
 
That is one way to do it if you want to use the standard metering provided. If you are prepared to invest in a VU meter plugin there is a another way to do it.  It will be a little more accurate.  I am assuming you want the ref track level to match your main mix.
 
 
 
 

if you are trying to MASTER your mix to match a reference track,
you will need more going on than simply matching up fader levels.
 
if you are simply bringing a reference mix DOWN in volume, to compare to a pre-mastered (or un-mastered) track, i use my ears, and not meters.
 
the meters are helpful, but the meter shows pure energy, whereas your ears tell you the 'apparent' volume, which musically speaking, is more important.

UltraBra the rms reading on the meter is that little line that hovers down on the scale. The top part are the peaks and that line lower down is the rms value.  Ignore the numbers at the bottom.
 
A better way is to get a VU meter plugin and set its calibration level so your Sonar mix just reaches 0 dB VU. Then adjust the reference track fader to do the same.  This is much better because you are now seeing something that is much further up the scale  (eg close to 0dB VU)  and hence easier to read and see.  You will get it closer this way.  Reading an rms reading very low down on a meter scale is a little harder.  And Sonar also shows the rms level 3 dB lower as well which does not help either.
 
The VU is very close to our ears but yes of course use your ears to fine tune.  Dave  is right too and I thought of it later and that is to insert a Loudness meter over your mix and match them that way.
 

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