frequency range for instrument vs speaker

If you think you can just buy a subwoofer, drop it into your living room and add an octave to the range of your music, then you are deluding yourselves. Room volume and size plays a much greater role in the low frequency response of a stereo system than with the higher voice range frequencies. Just like discussed, speakers can have a perfectly flat frequency response in an ideal anechoic environment, they do not quite achieve that flat response line in a real world listening environment. Perfectly flat response is a bit dull and boring anyway. I know, I tried that once years ago. I worked hard on my room with an analyzer and anechoic panels to make a flat response at my listening position. It sucked the life out of the music. btw- I had speakers back then had a 20-20k Hz range. I found the bass sounded better way into the next room as compared to my listening position.
When you add a subwoofer to your system and things seem to go deeper, that's mostly because it is reinforcing the 30-40's Hz range. You are not going to hear 20Hz from 12 ft back, ie. not at the same SPL level as the higher frequencies. That wavelength is over 56 feet long. Sure you can fold it over and reflect it back, but you better have some sturdy walls to get efficient reflections and the distances better be just right so it is at the correct phase angle at your ears. Even the 30-40 Hz range have wavelengths over 20ft long so their SPL levels at 12 ft back are not going to be as high as levels in the voice range without some boosting. Just try listening to the grand pipe organ from 12 feet back sometime. You won't hear the low pedals that close to the pipes nearly like being much further back in the building.

06-23-12: Tonywinsc
If you think you can just buy a subwoofer, drop it into your living room and add an octave to the range of your music, then you are deluding yourselves.

Why do I bother qualifying my statements with phrases like "properly blended" in my posts if you bulldoze over them like I never said anything at all. It's not like placement of a 350-lb. pair of full-range speakers with spikes is a piece of cake either.

OF COURSE you have to take special care in placement, phase adjustment, crossover adjustment, and level adjustment. Who on this forum wouldn't know that? I've seamlessly incorporated seven subwoofers into various systems in the past 7 years. I had a pair of subs in my living room and after living with them a few months, took about 4 hours to reposition them and re-adjust their settings. It was well worth it. I can now play large scale orchestral works (Berlioz, anyone?) on this system with engaging and credible reproduction.

Blending subs is a pain in the ass that can take anywhere from 2-4 hours to several days. But if it saves you $5K or more compared to the equivalent passive full range speaker, it's easily worth it.

As for the wavelength argument, my small towers are in an open architecture living room. There's almost no limit to how long a soundwave can form in my house interior--across the LR, up the stairs and down the hall, or across the living room, down the stairs, and out to the 18x22 media room.

Here's another thought: regardless of the size of the venue, if you have a subwoofer putting out a 25 Hz frequency, even if you're sitting well within the fully formed wavelength, the frequency is hitting your eardrums (and flapping your pantsleg) 25 times per second, and your brain will perceive it as such.

By your argument we couldn't hear bass below 180 Hz (about F below middle C) from a car stereo where the maximum interior dimension is around six feet.. Psst... we can.

My Vandersteen 5A's have a bunch of pots in the back that adjusts frequencys from the very low bass to the midbass. Richard himself helped me with my setup and told me that the goal was NOT to get a flat frequency response...just s pleasing one. Flat frequency response is a-musical.

06-23-12: Tonywinsc
Johnnyb, you explained it well. It takes a lot of effort and work to get it balanced across the broad spectrum. ... Like you said, you have to work very hard to balance all of that out and get it to work. You are taking great pains to get the reflections and the sources to all come together at the listening position. I still doubt you can achieve a balanced 20-20k in a small room.

Sorry; I have a nasty virus right now that's got me grumpy. You've been gracious and make good points. An advantage of the stand mount/subwoofer approach is that if you have to put your system in a smaller room you can dial back the subwoofer(s). Even a JL Gotham G213 can be turned down to reasonable levels in a small room, but you can't do that with a pair of Wilson Alexandrias (or other passive large full-range speakers) which will inevitably overload a small room.