Paolo,

You've just said that you have an 8 channel system defined, and you're asking the system do something it isn't designed to do, ie to only provide filtration on the front trio of speakers (not something I would personally consider) and to do so such that the target decay time is dramatically lower than the midband.

To do so is going to dramatically skew your results so that your midband is going to "hang" in the room compared to your low frequency, especially when you introduce the level of disparity that you are talking about introducing.

To be honest with you, I think all of this is window dressing until you work on the room and get some room treatments installed. They needn't be ugly, in fact some of the RPG products are lovely (and priced that way too). Until you do so, this is all pretty much an intellectual exercise.

Best,

Surround Music Fan/Computer Geek/Curmudgeon in training.
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