I have seen that thread and amazing work especially since he is building it from scratch! Winding your own VC is a pain in the neck! Mighty investment I must say! On another note, Don Keele's CBT line array apparently fills the room just like a bending wave speaker and not too sensitive to off-axis changes.
If you have a small room with lots of furniture and carpets, the effect of Bending wave speakers will be short and underwhelming and the same room much emptier the effect will be over-whelming. Although this is true of any speaker, the 360 degree propagation will make things a mess more than one can imagine.
There is a couple of limitations to a bending wave speaker and this is from experience. Firstly the diaphragm will have to be in a particular shape, since perfect cylinders or square & circular surfaces(in the case of exciters) will have the same modes & introduce resonances high into the frequency range. Therefore you can only do with certain shapes like rectangular or conical like this or the Walsh driver. Also with small rooms, I would just not invest in these overpriced stuff because a speaker with a constant directivity wave guide with a low frequency X-over will be equally good!
I have been meaning to buy a lot of cheap drivers, cut their diaphragm off, remove the dust cap and attach slightly thick chart paper, in a conical shape with no contact at the apex, slightly above the voice coil and make an array of sorts but now I have blown my balance on living a life. Hahaha! Enjoy people...
