Yes, that is true, but typical car subwoofer boxes usually have volumes much smaller than optimum. If those super-woofers are working in the proper volume, air nonlinearities are not an issue. I have build several subwoofers with those super-woofers (Audiobahn 12" used to come in a wooden crate and weights a ton!) - all of them have highish Qts parameter and require big box volume.
PA drivers will require considerably smaller boxes than 'hifi' drivers - my 18" Q 0.5 subs are 55l, and the 21" Q 0.6 subs will be 130l.
I am of the firm opinion that tight-sounding bass (ok, 'fast' if you insist!) is dependant largely on low energy storage, which favours sealed enclosures.
Move a lot of air - GENTLY!
I am of the firm opinion that tight-sounding bass (ok, 'fast' if you insist!) is dependant largely on low energy storage, which favours sealed enclosures.
Move a lot of air - GENTLY!
Yes, that is true, because PA drivers usually have relatively small Vas - consequently relatively small boxes. Big boxes are difficult to move for every live event - that is a big no-no in the PA world. Thiele-Small parameters of PA drivers are carefully balanced between low enough frequency cut-off, high efficiency and not-so big boxes.
I have built and sold a number of subwoofers with 18" PA woofers in about 60 liters sealed boxes - customers were delighted with the sound quality (tight bass).
In that case you'd want large enclosures to absorb all that energy, regardless of what Qts driver you use. I guess you could use eq to fix the response but you initially have an issue with ringing being that your Qtc is above critical damping.
Vented enclosures have no issues as long as you keep the response well above vent tuning. I think box pressure is lower than equivalent sized sealed boxes, in some of that area, then spikes around fb.
Sorry weltersys, are you complaining that I never saw, or didn't note, the quote you provided? Thank you though, regardless.
I check the sag of the PR on a regular basis. It's easy to just put you hand under there to feel it. The early versions of these speakers would sag very quickly, the later versions seem to last a very long time. I have two NOS CSS PR ready though.
Agreed. A rule of thumb I was given in the '70s by a noted British loudspeaker designer with whom I used to work was not to exceed 5% compression in sealed enclosures. Very drivers can achieve this in my calculations of low-Q enclosures, save the aforementioned silly kids' car system speakers (with a metre or two of Xmax) mounted in a lunchbox...