This can be much more effective than passive traps ( at least 10 and probably around 100 times more effective than passive broadband absorbers for equivalent size ). Special specific tuned tubes traps with helmoholtz tuned resonance will not be able to compete either. Looks like a great product but I have not seen this before - thanks for bringing it up.
One caveat, however, this is a speaker and like all speakers it can add lots of audible distortion (most subwoofers have terrible distortion levels of 20% and much more at the low frequencies below 40 Hz - only the very biggest subwoofers and with the most expensive drivers will approach audiophile distortion levels of 1%) So it would be great to knock out a room mode but not so great if it adds audible harmonic distortions at higher frequencies...
Based on what Bag End say it appears that this is recommended after regular passive acoustic treatments have been added. (i.e it is not the "one-stop answer to all needs" but is part of an overall solution which might also include a PARC and plenty of bass traps and wall treatments.)
FWIW - one Daad bass trap is not enough - unfortunmately size matters. I have four massive GIK tri-traps ( corner traps that are similar to DIY "Superchunks" ) and while it makes a big difference in the mid bass and lower mid range even four of these monsters does little to tackle the sub 50 Hz frequencies although I believe the biggest benefit is the NULLS.
I use a PEQ on my sub to tame the worst humps and it is not necessary to go for a flat bass response - often this sounds plain wrong and lacks life, IMHO. It is the improvement from taming 10 to 20 db peaks to within about 6 db of flat which is were the most imporvement comes from electronic notch filtering. I think the big problem for people who use ONLY electronic filtering to tame peaks is those nasty pesky persistent NULLS. Only broadband acoustic treatments distributed all around the room (all four corners) seem to work. The NULLS are actually the worst nightmare as the sound disappears...a particular bass note on a riff can nearly disappear - completely changing the sound of the music. IMHO the more andf different type iof treatments you can throw at it the better.....remember that in order to hear a note you just need to ensure some of the harmonics make it through clearly and the worst case is when all the harmonics of a note are simultaneously supressed...for exampe a null at 36 Hz and again at 72 Hz. The more varied your approach to tackling the room modal issue the better chance that nothing knocks a particular note dead!
