Originally Posted by kgveteran
I’m gonna take a good look at the boundries.... this is an interesting perspective.
We read all the time here of room boundary issues, why couldnt i “create” a boundary issue with purpose, a BSC type thing
I think it would be worth your while to do that. I think we all know that two thicknesses of 5/8" sheetrock, with no insulation in between, can create boundary gain, as that is the typical construction of an interior wall or partition. Two 5/8" or 3/4'' thicknesses of plywood or MDF, with an air gap between them and the boundary wall shown in your photo, should certainly help to lower the frequency response of your center channel. In any event, it will be pretty easy to tell whether or not it works.
My concern about distortion, to which Craig replied, really had nothing to do with Audyssey. As he said, Audyssey stops EQing at the F3 point of a speaker. But, either with Audyssey on, or Audyssey off, your own volume boosts will make the center channel play frequencies below 110Hz louder, if you lower your crossover to 80Hz. Doing that won't harm your speaker, but if you try to make it play lower than it really can at that particular position in the room, and at any very significant volume levels, you may pick-up some distortion as it tries to play frequencies down to about 80Hz.
I think that can especially be a concern for the center channel, as it carries a good bit of low-bass content, and as many HT owners like to bump the volume of their CC's in relation to their other channels. With overhead speakers for instance, dropping crossovers below their measured F3 points is less of a concern, because they won't carry a lot of low-bass content to begin with. But, the CC does. And, any loss of clarity at all might be more noticeable in the channel that carries nearly all of the dialogue.
Of course, you can always experiment to determine whether there is any perceived loss of clarity from the CC, with an 80Hz crossover, at higher volume levels. If not, you are good to go. But, if there is, I might try to find a way to give the CC a little better low-bass response, with a baffle board, so that I could use an 80Hz crossover.
If you can't find a way to drop the frequency response, then I would agree with Craig that there would be no real harm in lowering your crossover a bit, anyway. But, in that case, I might be conservative, and only drop it to 100Hz, or to 90Hz. If I did drop it to 80Hz, I would want to be sure that I wasn't trading volume increases for clarity decreases. As with almost everything in audio/HT, there is some trial-and-error, and some potential compromise involved, in the settings we pick.