My PV2 is almost as close to the front as possible. Looks like only maybe 1" added to the front and a longer piece at the back.

Definitely sounds like having it mounted closer to the front tones down the resonance a bit. I am noticing with mine that the temp and/or humidity outside seems to make quite a bit of difference to the sound. When it is cooler and wetter it seems to be louder.

ISCE