Rules for matching subwoofers to room size

Now we are talking - thanks all for your input.

I actually do not have the mains (or really much of any of the equipment) I will use in this room yet. Most of my current two channel system will go to my new modest sized living room and I will start from scratch with gear for the new larger audio/video room. I will do my best to set the new room up with as few acoustic problems as possible from the start, and then demo/buy/sell/trade until I find the speakers I like in that space. I am definitely leaning towards floor standing speakers (and amps that can drive them) that can honestly go down to at least 40Hz without straining, and then supplementing lower bass with a sub - thus this thread.

I have a small Klipsch sub in my current small (12'x14') theater room, and while it is a clean little sucker, it will not go much below 30Hz nor pressurize the new larger planned listening room to the levels I seek. I have worked to integrate my current sub with various configurations of speakers and amplifiers - so am pretty handy with a spl meter and test disk. To be honest, even with cutoffs above 80Hz I have a hard time locating the source of the bass once the sub's position and phase is dialed in properly.

The reason I asked the original question is that I believe I have read that there is an inherent limitation on the bass frequencies that can be reproduced related to room length and to a lesser degree room volume. I guess what I really meant - is in a 20 foot long room, how low of bass notes can I reasonably expect to reproduce? And, if there is a limitation, what is the point of getting a sub that can in theory go down to 19Hz if my room can only allow me to hear or resolve 25Hz? I am way off here? Your continued patience and input much appreciated.

Thanks, helpful.

Funny you should mention the Revel F52 - was considering a pair of used F32's for the fronts. Budget for whole 5.1 or 7.1 speaker system including sub around $5K+- used. I have some large and small bookshelf speakers that could serve as surrounds for a while - so really only looking for 3.1 system within that budget.

I think something like the F52 would need a lot of power to accurately recreate the lowest frequencies with the aplomb of a good subwoofer. They are also pretty darn big. But perhaps ditching the subwoofer for larger front speakers and a more capable amp would be a reasonable trade off. Then I a would only be looking for a "3.0" system plus breaking the electronics budget (also $5K not including screen) a bit on a stronger amplifier...

Thanks,

I like the the overall presentation of the Revels - the F52's are very nice and I think a good value in a full range speaker - not very far off the Salon Studio2 IMO. I spent a fair bit of time with the M22's and enjoyed every minute, but they are current hungry. Will probably end up trying a few different speakers to see what works best in my space. I do like that fact that Revels allow you to adjust the tweeter level and optimize sound for placement in the room.