Subwoofer guys - House curve or flat?

http://www.hometheatershack.com/forums/rew-forum/96-house-curve-what-why-you-need-how-do.html

Start with perfectly flat response and experiment with incremental adjustments toward your choice of target curves.

I ended up with a perfectly flat curve to 35hz and a gentle rise (+2-3db) down to 25hz, followed by a steep "subsonic" roll off. The difference between this and flat to 25 hz is rarely perceptible, but occassionally manifests as either a) slightly larger sense of the recording space or b) gently vibrating coffee table.

Marty

PS IME, response below 25hz will yield nothing beneficial for any program material in my music collection.

I have mine set to start rolling off on the top end at 25 Hz so tastes differ. I suppose that is why REL calls theirs a sub bass rather than a sub woofer.

Why roll it off on subsonic frequencies? Is there any reason besides saving sub amp power? The way I look at it is if it's on the recording, it should be reproduced. I figure it's like the vinyl argument, even if you can't hear it, you call feel it.

In my opinion what you want is flattest possible in-room bass without causing problems. How you get there depends on the sub's inherent response and the room acoustic situation. Note that once boundary reinforcement and modal effects are factored in, what may have started out as "flat" response is now far from it.

Duke
dealer/manufacturer

Duke said, "In my opinion what you want is flattest possible in-room bass without causing problems......... Note that once boundary reinforcement and modal effects are factored in, what may have started out as "flat" response is now far from it."

How would we know this? Is there any way to measure this?
If this is true what can be done to change it?

Bob

Nemesis

I filter subsonics because the odds are very very low that any such info is deliberately "on the recording". I don't need to hear the subway that happened by or,more likely, mechanical noise from my source (rumble)

I understand that some purists may disagree

Bob,

I use RTA to measure in-room response on-axis at the listening position
There are any number of devices out there for this purpose - or variations therein

Marty