@deep_333 wrote:
appreciate the info you provided....I have a couple of rooms in my basement for audio (no WAF issues), 1 for multichannel and the other room for stereo. Size of speakers and subs is not an issue (bigger the better).
Interesting, so you could experiment with two different subs approaches (more on that below) with no restrictions in regards to size.
I recently went up to a pair of the 18inch F18 Rythmik subs for my multichannel room, which go infrasonic, usable output down to 10hz, an entire octave below 20hz technically speaking...All you hear from the naysayers is.."There’s no content that hits that low or ya can’t hear that low", whatever. On the contrary, it’s flipping nuts, the impact these monster subs have on many tracks, that i have heard a thousand times. It’s a new phenomenon, lol....
Infrasonics is a big deal with movies (and even music, to an extend), no doubt, and those who haven’t heard the difference the octave below 20Hz can do here (with select movie source material) obviously don’t know any better. A pair of 15"-loaded high power capacity subs (direct radiating, sealed) crawling low enough would begin to give an indication of infrasonics, but the real impact and significance comes with much larger air displacement area - not intended as an effect per se, but rather reflecting the means of what is really necessitated at frequencies that low to attempt and approximate energy linearity and some kind of minimum headroom. Meaning, if one has the intention of trying to investigate on the importance of infrasonics in one’s home setup, be that with movies and/or music, it’s vital that a surplus of effective cone area - in addition to a lot of power (and proper concrete flooring and overall room construction) - is attained for this purpose, and for most audiophiles that’s likely a lot more than they imagine and care to implement in their homes. Which is a shame, because it’ll be a stone unturned (an important one at that) for many on what infrasonics can do to the experience of sound in general.
It is also perhaps a motivation to try out something different in my stereo room....like a pair of large horn subs! My current open baffle GR subs that i have in the same room are good for what they are, but, it’s more for precision (not for the visceral maniac stuff). Have you heard of these Devastator horns? I ran into a couple of AVS threads with guys talking about it....
I’ve heard of the Devestator subs, yes, though technically they’re not really horns but rather a high order bandpass design (basically ported) that utilizes the output from both the front and back wave of the cone, and which mimics suspiciously close the design of Josh Ricci’s Skram subs, just tuned lower and thereby bigger. If I’m not incorrect the front wave of the cone (the 21" driver is situated, and hidden inside the cab) shoots into a short, expanding slot (or horn), while the back wave is loaded via the bigger part of the enclosure into large, square ports. The output is then summed through the short horn/port sections. The important takeaway here is the higher efficiency compared to typical hifi-ish or even cinephile subs, which is also seen by their larger size (i.e.: Hofmann’s Iron Law), but they’re still good to about ~15Hz or so and would make an interesting ground of comparison to the lower eff. subs in the other room for you to embark on. Technically, my tapped horn subs are also a high order bandpass design, but here the front wave of the woofer fires directly into a compression section and then expands into a regular horn path that via its length dictates the tune of the design (which through the Devestator’s is done via the backwave into the ported cab section), which is why the core of the design is really a horn, and the backwave of the cone is situated close to the mouth area that will then sum with the wave of the horn.
If you want to up the efficiency factor further, while maintaining extension down into the 30Hz and (when corner loaded) even 25Hz area, non-truncated front loaded horn subs like the 12Pi horns or similar-ish iteration from John Inlow are the way to go. With this we’re talking a minimum of 105dB sensitivity, and they’re rather massive in size. Imagine the whole front section of the horn being one big mouth area, and it should give you an indication of the power at play here. Really though, it comes down to the sheer quality of bass which is utterly smooth, layered and immersive, and firing these things up to prodigious SPL’s (which requires very little power) the effortless force and presence is something to behold. Hifi subs are mere toys by comparison, sonically and SPL-wise - believe me.
The interesting thing for you will be comparing the importance of infrasonics, not least in music, from the low eff. subs with the more extension restricted higher eff. sub counterparts. Myself I’ve opted for the higher eff. solution (full click @25Hz, and rolling off from here) for both music and movies in a single listening space. The price of infrasonics is lower efficiency and a large sub count to add up on the necessary displacement here, and moreover there’s a sonic implication because lower tuned, direct radiating designs simply sound different compared to higher eff. iterations, not least when they have more or less hidden cones. The latter are inherently more musical to me, and to boot they energize the listening space very differently and more effectively than smaller subs.
It looks like they get down to 19hz, comes with all the flatpacks, i.e. seems to be a more complete easier diy kit. I’d hate to stare at drawings and start cutting wood from scratch, not have it be too much of a time investment.
It’s certainly a much easier process than cutting out the stuff by yourself, which would have also required the proper machinery in a dedicated space and preferably assembly experience.
