[bpape]

It depends on how, where, and with what you've treated the room.

You can in theory completely cover every surface of the room in narrow band bass absorbtion and have almost zero effect above say 500Hz. Not that this is desirable but it's possible.

Now, realistically, in a small room, one usually needs to use a more broadband solution simply because there is limited amount of space to deal with. On the positive side, modal frequencies in smaller rooms are higher in frequency.

The trick is to determine what the target decay curve should be based on size, usage, construction, furnishings, etc. and then come up with a treatment plan that will address SBIR, modal issues, early reflections, etc. but do so in a way to stay within the target range.

More to your question - if one simply takes some of the say 1 and 2" material in the room and converts it into 4 or 6" material, you're not changing the mid and high frequency absorbtion but you are adding additional low end control in the lowest few octaves.



Bryan