Why are the audio levels on my master track lower?

I have only one audio track on my timeline. There is only one audio clip on it. There is absolutely no processing/filters/effects applied to that audio clip on the timeline. Shouldn't the master track be the exact same level as the only track in my timeline? Is DR applying some kind of a limiter behind the scenes that I'm not aware of?

The summation of two identical signals of equal amplitude and phase increases the level of the resulting signal, hence the attenuation on the stereo Bus 1 to produce equal power output and equal perceived loudness. This is the result of Pan Law, in this case “-3dB compensation” being applied.

pan law is dropping the level
I edited because I originally thought you also had a mono clip on a stereo track, but the pan shows you haven't, but it looks a bit odd in the waveform display, but that's not anything to do with the level on the meters

Reynaud types quicker than me... it's so when you pan a mono signal across the stereo image it stays at the same perceived loudness rather than getting louder when it's panned to the centre, for the reasons Reynaud explained. Pan it completely to one side and the meters will match.

Ok, I see. Thanks so much for the explanation! The reason I was confused is because that's not how things work in Premiere.

So basically if I have a mono clip that's already been compressed outside of DR and it's peaking at -6dB, if I want it to still peak at -6dB once it's inside of DR I have to raise it by +3dB?

if I have a mono clip that's already been compressed outside of DR and it's peaking at -6dB, if I want it to still peak at -6dB once it's inside of DR I have to raise it by +3dB?

That is not necessary since the perceived level remains constant.

If you want to meet the same measured peak level then you'd need to adjust your master fader, or the channel fader. (or normalize the rendered file) As far as I'm aware Premiere Pro does apply a pan law of -3, so it should have been the same as in DVR, unless the project had a mono master bus..I'm not so on top of Premiere so don't even know if that's possible, but if you send that signal to a mono bus the measured level will be the same as the original file if the channel fader is set to unity gain