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Interesting, but definitely NOT small. The fan itself is small but it's not like you can just stick it in the room as is. You're neglecting the chamber through which it has to fire, which is IIRC a 9' or 12' long transmission line. Basically, it has to be mounted in the adjoining room, or an attic/basement, to work properly. Unless you prefer fan/motor noise to bass...

Personally, I want one. Bruce Thigpen is hardly a fly-by-nighter or snake oil merchant. His air bearing tonearm design is just plain genius, and I've always wondered why his planar speakers didn't get wider diffusion. (OK, they're ugly and unlike Magnepan barely marketed...) So that, coupled with reports from the RMAF demo written by people with their own giant I-B home sub installs, lead me to believe that this sub is the real deal. That being assumed, this sub seems like the perfect solution for a serious home audio or HT system, which can use large-bore high-efficiency "pro audio" woofers without worrying about their lack of deep bass compared to their ultra-high-resolution midbass and unparalleled transient response and still have a never-ending supply of deep bass.
 

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DS-21 said:
Interesting, but definitely NOT small. The fan itself is small but it's not like you can just stick it in the room as is. You're neglecting the chamber through which it has to fire, which is IIRC a 9' or 12' long transmission line. Basically, it has to be mounted in the adjoining room, or an attic/basement, to work properly. Unless you prefer fan/motor noise to bass...

Personally, I want one. Bruce Thigpen is hardly a fly-by-nighter or snake oil merchant. His air bearing tonearm design is just plain genius, and I've always wondered why his planar speakers didn't get wider diffusion. (OK, they're ugly and unlike Magnepan barely marketed...) So that, coupled with reports from the RMAF demo written by people with their own giant I-B home sub installs, lead me to believe that this sub is the real deal. That being assumed, this sub seems like the perfect solution for a serious home audio or HT system, which can use large-bore high-efficiency "pro audio" woofers without worrying about their lack of deep bass compared to their ultra-high-resolution midbass and unparalleled transient response and still have a never-ending supply of deep bass.
Very interesting, where can I find more info on his planars?
 
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If you've read the ECA link, you guys know my position on this. "What appears to be [an] industrial bathroom fan is actually" ... an industrial bathroom fan. A few quotes from the very enlightening article, followed by a bit of commentary :

"Most powerful subwoofer in the world" ... subs don't generate power, they convert it.

"Most powerful subwoofer in the world, achieving FLAT response down to 1Hz" ... frequency response and power are two different things.

"Remember, response is FLAT to 1Hz, meaning there is virtually no distortion" ... frequency response and linearity are two different things.

And yes, the article states that Bruce Thigpen confirmed everything posted.

Well, here's another quote that's much more meaningful in this context : "There's one born every minute." :rolleyes:
 

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werewolf said:
If you've read the ECA link, you guys know my position on this. "What appears to be [an] industrial bathroom fan is actually" ... an industrial bathroom fan. A few quotes from the very enlightening article, followed by a bit of commentary :
While obviously I haven't read the link at the Ignorant Tightass Club, not having privileges there, you're wrong. If you've read the HTGuide link that started with a demo by someone who knows deep bass well, you'd have learned that Mr. Thigpen's sub is more like a small helicopter rotor connected to a voicecoil than a bathroom fan.

The contradictions in that article don't mean anything. It was probably written by someone of limited technical knowledge, not BT or someone who knows what he's doing.

werewolf said:
"There's one born every minute." :rolleyes:
Except that, at least in the limited sense of a single-descending-tone demo, it appears to work spectacularly. Obviously, we'll learn more at CES; if BT continues to demo it playing single tones by themselves, then let the alarm bells ring. Even if the concept is sound, the implementation will obviously not be up to scratch yet. But given his track record and the fact that the demo he's conducted thus far did exactly what he claimed it would I think there's a lot less Barnum here than would perhaps appear at first glance. What is, however, fairly clear is that given the noise-control demands there's no practical car-fi application for this sub.
 

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So how does this actually work.....If it works like it does in my head, with the fan blades spinning, then how responsive is that thing to changes in frequency, as i beleive its harder to get something to move with cincrifical force than linear force. And changes in fan speed would need to be highly controlled to be any short of accurate.....Just dosent seem to me to be musical, Sure it could work for tones, but low low low stuff, i dunno.

Then again i've never looked at figure out how the PG cyclone works.....But linear movement seems more effecient to me than cincrifical with transient music.
 
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I'll never put more weight in hearsay than physics. How does one define (or, for that matter, measure) spectacular performance? Golden ear audiophiles who can hear 1Hz? Couldn't be excessive vibrations or harmonics that would be, oh I don't know, in the actual range of human hearing? Might be an impressive experience, if true at all, but certainly not fidelity ... or rather, audible fidelity. Strange no measured frequency response plots, distortion graphs, etc. were posted. I'd love to see a link with measured performance ... is there one? Surely someone doesn't build such a thing without measurement of some sort.

No matter, "believe" what you will. I've got a set of super tweeters ... response from 80khz to 300kHz ... that will only set you back $10K. Gotta use the right wires first, of course.

Oh yeah ... might want to mention that very few (if any) analog-to-digital converters used in audio, or for that matter any electronic signal paths in the entire recording chain ... have a flat response down to 1Hz. Wonder why? So, sadly, the true performance of the "world's most powerful subwoofer" can never be realized with existing electronics ... or ears.
 

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demon2091tb said:
So how does this actually work.....If it works like it does in my head, with the fan blades spinning, then how responsive is that thing to changes in frequency, as i beleive its harder to get something to move with cincrifical force than linear force. And changes in fan speed would need to be highly controlled to be any short of accurate.....Just dosent seem to me to be musical, Sure it could work for tones, but low low low stuff, i dunno.
I'm not sure how it exactly works but from what I've read that the Fan spins at a constant spead and the blades tilt for whatever frequency it needs to reproduce. But that's about all I really know or understand about it. I'd like to know more about it even though I can't afford it but if I ever win the lottery or something it might be worth trying out haha.

Ryan
 

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|Tch0rT| said:
I'm not sure how it exactly works but from what I've read that the Fan spins at a constant spead and the blades tilt for whatever frequency it needs to reproduce. But that's about all I really know or understand about it. I'd like to know more about it even though I can't afford it but if I ever win the lottery or something it might be worth trying out haha.

Ryan
Yes this is how it works.
 
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DS-21 said:
While obviously I haven't read the link at the Ignorant Tightass Club, not having privileges there, you're wrong. If you've read the HTGuide link that started with a demo by someone who knows deep bass well, you'd have learned that Mr. Thigpen's sub is more like a small helicopter rotor connected to a voicecoil than a bathroom fan.
Change the name "voicecoil" to "fieldcoil", and you've precisely described an industrial fan.
The contradictions in that article don't mean anything. It was probably written by someone of limited technical knowledge, not BT or someone who knows what he's doing.
As I've already posted, "BT" approved every word. Read the article again.
 

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DS-21 said:
While obviously I haven't read the link at the Ignorant Tightass Club, not having privileges there...
Now that is comedy right there... You should pursue a carreer in standup comedy ;)
 
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Yep, I think he's referring to the "club" he chose to join, of his own free will ... but now we won't let him play anymore, so therefore it's an "ignorant" club :p

Sorry DS, but hey you started it ... lol !! :D :D just playin' dude.

Regarding this sub, I've got no real, vested interest one way or the other of course. Just my nature to be skeptical of outrageous claims I guess. And being an engineer, I need some measured objective data to substantiate subjective observation.
 

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Yes it's a fan, the same way that a traditional cone woofer is a thin peice of paper or metal. I don't see where you are going here, werewolf.

It spins at a constant speed while the blades tilt to produce whatever frequency it needs. It should be able to produce a nice amount of output, too. Though I've never seen or heard it in person.

The claim that humans can only hear between 20-20000Hz is outdated and in the past decade it has been shown that humans can hear between 5Hz and 40000Hz if something is played loud enough. Also, subsonic and ultrasonic sound waves modify the sounds in the audible range. Even a test tone in either the subsonic or ultrasonic range that is clearly inaudible, our brain still responds to it according to MRI scans.

Music is not only heard but should be felt by our chest cavities and the hairs on our skin. Join team megasubwoofer!
 
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cotdt said:
Yes it's a fan, the same way that a traditional cone woofer is a thin peice of paper or metal. I don't see where you are going here, werewolf.

It spins at a constant speed while the blades tilt to produce whatever frequency it needs. It should be able to produce a nice amount of output, too. Though I've never seen or heard it in person.

The claim that humans can only hear between 20-20000Hz is outdated and in the past decade it has been shown that humans can hear between 5Hz and 40000Hz if something is played loud enough. Also, subsonic and ultrasonic sound waves modify the sounds in the audible range. Even a test tone in either the subsonic or ultrasonic range that is clearly inaudible, our brain still responds to it according to MRI scans.

Music is not only heard but should be felt by our chest cavities and the hairs on our skin. Join team megasubwoofer!
The information about the frequency response of the human auditory system is not outdated. The observation that we can hear higher or lower, if the signal is loud enough, does not outdate that info. Any physical system that has a limited frequency response, will demonstrate a "rolloff" associated with that limited response. If I cross a driver (lowpass) over at, say, 1kHz ... even with a steep 4th order response ... you can still hear music (or tones) coming from it at 2kHz, 4kHz, etc. if the signal is "loud enough" (A 4th order response is attenuated by 24dB, but not eliminated, an octave away). It doesn't mean the crossover isn't working as designed, and it doesn't mean crossover understanding or technology is outdated.

Where am I going with this? The entire audio reproduction chain ... from original musical event, through rather sophisticated electronic and storage elements, and finally to our ears ... is a bandlimited system, like it or not. I know my auditory system is not capable of any significant response down to 1Hz ... it's been measured. And I know with complete confidence that I can point to several other elements of the chain that are flat down to nowhere near 1Hz. So even if the driver behaves as advertised, it's utility is severely hampered in any reproduction system, of which our ears are an integral part. Armed with that knowledge, we can blindly (blindly, because so far I haven't seen any objective measurements) believe claims about drivers responding flat down to 1Hz, and impressing audiences. Or, we can believe it's a really, really expensive fan ... capable of shaking room walls, but incapable of high fidelity audio reproduction.

Since there's no scientific foundation for the performance of this advertised product (that I've seen, anyway), it would seem that faith is all we've got. Believe what you will.

I just have one question (well OK, two). If the driver were advertised to respond all the way down to zero Hertz (i.e., DC), would you believe that just as easily? Why, or why not?
 

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werewolf said:
Change the name "voicecoil" to "fieldcoil", and you've precisely described an industrial fan.
You mean industrial fans have blades mounted on a suspended moving coil that can alter their pitch, acting in a positively-driven electromagnet? That's what I understand by "field coil", as used by many extremely expensive old drive-units (and some newer ones) in lieu of permanent magnets.

werewolf said:
I'll never put more weight in hearsay than physics. How does one define (or, for that matter, measure) spectacular performance? Golden ear audiophiles who can hear 1Hz?
"Hear" one 1Hz with "golden ears"? Surely you know better than that. Try "golden facial and chest bone structure". There's scads of research on human perception of very low frequencies, and while I don't remember the exact numbers off the top of my head I believe the "Fc" of the "mechanical crossover" between hearing with one's ears and "hearing" with the bones of one's face and chest is somewhere in the area of 40Hz. That's why headphone bass sounds so strange compared to the real thing despite the documented presence of lots of LF fundamental in most decent headphones, and likewise why canalphone bass sounds so different front circumaural headphone bass, which at least hits the hairs on the outer ear and some facial bones. It's also why listening to good headphones with a sub blended in is so much more realistic-sounding, if perhaps utterly in contravention of headphones' usual purpose.

Now, whether or not a human being can differentiate a 1Hz sine wave from a sine wave 3 octaves higher (i.e. 8Hz) is a different issue altogether. I don't know the answer, but I suspect that at the same (bloody high, to register at all) SPL the 1Hz wave would merely appear to be a less intense pressurization. (I do know that differentiating sine waves below 40Hz or so using canalphones is harder than doing so using circumaural headphones, which in turn is much harder than doing so when listening to a good sub.) However, as there are clearly recordings with massive content in the 7-8Hz range - I'm writing of the infamous Kunzel/Cin. Pops recordings of the 1812 and Beethoven's "Wellington's Victory" on Telarc, neither one of which sadly has merit beyond said deep bass content, as well as many recordings of the Royal Philharmonic when the Tube passes by - and lots of music with fundamental in that range, too. Maybe 5-6 years ago (before the formation of Lambda Acoustics, I'm pretty sure) Nick McKinney posted some results he got analyzing kick drums using Cooledit, and found signficant output in the 10Hz range.

But even ignoring the debatably differentiable (but NOT debatably perceivable, for what are earthquakes but extremely low frequency waves of extraordinarily high amplitude?) VLF content, your comments about bandwidth limitations in every physical system do not detract from the utility of a supermegasub, but in fact reinforce the notion that it is something worth pursuing if fidelity is the goal. Bandwidth improvements in one sector of the chain can force bandwidth widening in other parts. Thirty years ago nobody needed a speaker that could play much below 40Hz, or much above 12kHz, because all most people had to listen to were two formats of mediocre FR, FM radio and vinyl. Then CD came along and all of a sudden you could have more bass without the needle jumping out of the groove and treble that even the lightest needle could not hope to resolve with a high degree of precision or accuracy. So if loudspeakers capable of plumbing the depths start to arrive, then the rest of the chain may well follow.

But honestly that's not why this sub so interests me. I'm less concerned with the ultimate bandwidth than I am that the lowest point falls below anything I'd like to hear. For maximum fidelity, would you rather have a system that was at its half-power point at 4Hz or at 20Hz? Which system is going to give you the full effect of a well-recorded 16Hz organ pedal, one that's 3dB down at 20Hz or one that doesn't reach its half-power point until two octaves below the lowest frequency of interest?

As for measurements, I'd like to see them, too. And I suspect in due time we will see meaningful data. Given his no-BS track record and unconventional innovations past I'm inclined to cut BT a lot more initial slack than I would 99% of the audio industry. For that matter, I don't think we've seen much in the way of measurements of Tymphany's forthcoming LAT's either, but simply given the talent behind them do you doubt that they're going to perform at least as well as claimed when the finished version is unveiled?

werewolf said:
No matter, "believe" what you will. I've got a set of super tweeters ... response from 80khz to 300kHz ... that will only set you back $10K. Gotta use the right wires first, of course.
Given that bog standard 12AWG shotgun has a bandwidth of something like 1.8mHz, I don't think wires would be a problem for any supertweet. ;)

That said, I'm still very much on the fence about supertweeters, by which I mean real ones operating in theory from ~20Hz through some of the next octave(s). On the speakers using them that I've heard (Tannoy TD12, Kef Ref 203) I thought they caused as many problems (or more) than they solved compared to previous generations of both speakers, although there are a lot more variables there than just the presence/absence of a supertweet of course.

And for the record, I coined the term "Ignorant Tightass Club" long before some feckless reactionary twit decided that a point-of-view more informed than the bigoted, extremist right wing idéologie de la maison was unwelcome there.
 
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DS-21 said:
But even ignoring the debatably differentiable (but NOT debatably perceivable, for what are earthquakes but extremely low frequency waves of extraordinarily high amplitude?) VLF content, your comments about bandwidth limitations in every physical system do not detract from the utility of a supermegasub, but in fact reinforce the notion that it is something worth pursuing if fidelity is the goal. Bandwidth improvements in one sector of the chain can force bandwidth widening in other parts. Thirty years ago nobody needed a speaker that could play much below 40Hz, or much above 12kHz, because all most people had to listen to were two formats of mediocre FR, FM radio and vinyl. Then CD came along and all of a sudden you could have more bass without the needle jumping out of the groove and treble that even the lightest needle could not hope to resolve with a high degree of precision or accuracy. So if loudspeakers capable of plumbing the depths start to arrive, then the rest of the chain may well follow.
I agree.

But honestly that's not why this sub so interests me. I'm less concerned with the ultimate bandwidth than I am that the lowest point falls below anything I'd like to hear. For maximum fidelity, would you rather have a system that was at its half-power point at 4Hz or at 20Hz? Which system is going to give you the full effect of a well-recorded 16Hz organ pedal, one that's 3dB down at 20Hz or one that doesn't reach its half-power point until two octaves below the lowest frequency of interest?
Not a huge issue, in my experience. The frequency response differences are quite easy to calculate, and equalize if necessary.

As for measurements, I'd like to see them, too. And I suspect in due time we will see meaningful data. Given his no-BS track record and unconventional innovations past I'm inclined to cut BT a lot more initial slack than I would 99% of the audio industry. For that matter, I don't think we've seen much in the way of measurements of Tymphany's forthcoming LAT's either, but simply given the talent behind them do you doubt that they're going to perform at least as well as claimed when the finished version is unveiled?
Track records don't impress me. Rigorous adherence to the scientific method does. Then again, I've never been one for name-dropping. There's simply no room for gurus in science.

That said, I'm still very much on the fence about supertweeters, by which I mean real ones operating in theory from ~20Hz through some of the next octave(s). On the speakers using them that I've heard (Tannoy TD12, Kef Ref 203) I thought they caused as many problems (or more) than they solved compared to previous generations of both speakers, although there are a lot more variables there than just the presence/absence of a supertweet of course.
Very easy to prove that, whatever tricks supertweeters may perform, faithful audio reproduction ... with vinyl or CD's ... is not one of them. At least prior to the introduction of SACD & DVD-A, the audio chain has been a sharply bandlimited path. No two ways around it. It's physically impossible for CD's to contain any information above 22.05kHz, for example.

And for the record, I coined the term "Ignorant Tightass Club" long before some feckless reactionary twit decided that a point-of-view more informed than the bigoted, extremist right wing idéologie de la maison was unwelcome there.
Got a link indicating the coinage date? Before or after you joined the club? And for the true record, all informed points of view ... left or right ... are welcome on ECA. Check the ratio of active members to banned members (unless one can think of another OBJECTIVE figure-of-merit?). What's not welcome is large-vocabulary/small-minded fashionable prejudice. In any case, I had nothing to do with your, or anyone's, ban.

Regarding this sub, I've not got much more to add. No vested interest, one way or the other. Here's a diyaudio link, more info ... and perhaps an indication that I'm not the only skeptic :

www.diyaudio.com/forums/showthread.php?s=&threadid=67028&highlight=
 
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