Good Used Speakers ($8K-10K) For A Little Listening Room

The wavelength of 20Hz is 17 meters. So by your logic almost no listening room can produce 20 Hz. I propose that most rooms, even small rooms, can support 20 Hz simply because acoustic waves can bend around the boundaries of the room. It’s the same reason why the acoustic Schumann Frequency of 7 Hz - the wavelength of which is obviously much longer than 17 meters - can be produced in any size room. An more extreme example is the electromagnetic Schumann frequency that has a wavelength equal to the circumference of the Earth, 25,000 miles. Yet the Schumann frequency generator produces the electromagnetic 7.8 Hz frequency in any size room. Hel-loo!

Your comment is irrelevant. I did not say you cannot pump deep bass into a room. What I said was that it will not sound right, and for two connected reasons. The first is that the smaller the room, the higher the Schroeder frequency (about 280 Hz in this room) and hence the frequencies of the room modes (not to mention their upper harmonics). The second is that the higher the frequency that you try to equalize, the narrower the listening spot. If you want good deep bass you need a large room with a low Schroeder frequency. And avoid square rooms.

This is what I wrote (and for everybody to see): "Good deep bass in a small room is quite simply impossible." That is simply true for the reasons I gave.

Ah, now you changed your post: you added the 'good' that you did not include before. That is dishonest and misleading. But now you reinstated the word 'good' your comment is no longer relevant because it does not address the quality of the bass. And that precisely was my point.