Wilson Benesch Torus Infrasonic Generator

That thing at the bottom sure looks like a cone driver. If not a subwoofer, what is that thing?

in the pdf...i've noticed a ton of promotion, but nothing in the way of measured performance...do the 7" drivers that they use (in their other speakers) incorporate linear motor technology?...they also seem to be exploiting a few subwoofer/driver myths in their presentation and some sweeping generalizations...but lets see what this thing will do on the bench or in a room, which they seem to ignore as one of the biggest factors in transient response...

So whatz it do ?

From a HT stand point, throw WOTW at it and we'll see.....

How much is it ? Frequency response ?

Looking at the FR graph from the German review PDF, doesn't look that impressive. The response looks to start dropping off around 40 Hz, and pretty steeply from there towards 20 Hz. If they are using some new technology, that's great, but people looking for flat response to 10Hz will probably be very disappointed. Although I don't read German, so maybe one of those knobs on the external box will get you flatter response down low without compression at higher volumes?

looks like maximal compression levels of 101 and 98.5 dB for 45 and 35 Hz respectively...this is definitely not a HT subwoofer, if these results are accurate...looks like there may be two tuning modes 35/45 Hz? or 70/55Hz crossovers?...looks like a steep rolloff at the bottom to boot...this will definitely affect system ringing...i.e. transient response...this would be too shallow for even a music only system ...most larger floorstanders will certainly compete with this driver system...$9500?

And if you can't afford two Toruses--as I certainly couldn't--the Minis will do just fine all by themselves, though, once more and for the last time, they won't go down below 20Hz with the flat response they have above 40Hz and they won't play in the 20-40Hz range with all of the authority you hear on real instruments capable of playing notes this low. Something has to give with a two-way; that's just fact and physics. If you listen, primarily, to power music, you may be left a bit wanting. But only a bit, depending on amplification. (I am told, by Alon Wolf no less, that the $40k ARC 610T makes the Minis sound as if they have a subwoofer.)

exactly what is power music? if the Mini's claim to fame is chamber music and symphony, do note that organ and lower piano are around 16 Hz and 27 Hz, respectively...and the Mini's dive where...around 40 Hz...i don't mean to be sarcastic but
it is my contention that a bookshelf speaker of the caliber and price of the Minis should be able to do all things well...and all the boasting about the board flat frequency response...what happens when you put it in a room that is'nt acoustically treated up to the wazoo? That flat FR won't matter so much then...the number and severity of resonances in the room will dictate the sound signature to a large degree...I'm not saying that the Minis are'nt technologically cutting edge, i'm just saying that "some" loudspeaker designers would have you believe that the only thing that matters is the speaker itself...that's just not factual...

on AVguide, for the Torus, i don't see anything of mention as far as GP measurements THD tests, impulse response, power compression, etc. etc...just subjective opinion which "usually" comes off with a certain degree of bias...the Torus is an achievement, no doubt, but transient response is only one facet of VLF production...as a matter of fact, as you pull the crossover frequency lower, you increase the time delay between the region below it and the region above...phase shifting becomes more pronounced as frequency falls...of course, the severity of this shift will be dependant on the Q and cutoff rate of the filter.

Yeah I'd love to see a thorough testing of this thing, with all switches, etc. taken into account.

no problem...did'nt mean to come off abrasively...i'm sure the Minis employ SOTA materials...great craftsmanship is evident, beautiful speakers...too rich for me though...i'll have to be content with my lil ole analytical Klipsch RB-35's ...as i said, the Torus is an achievement, but there are a ton of high SPL, 10 Hz'ers around here...and it takes some convincing with new products such as these...

hello WSLam,

I am sorry, to correct you regarding Japanese test of loudspeakers in issue 156 of Stereo Sound (fall 2005):

Magico Mini indeed had much good THD results, but actually it was only 4th place in this category, behind German Physiks, YG Acoustics Anat, and Wilson Benesch. Also, the tester Ishii-sensei wrote that in problematic 3rd harmonic measurement, actually best were JBL K2, Sonus Faber Stradivari and YG Acoustics Anat.

In total score (including all - SPL, SPL at long distance, off-axis and THD), 2 winners were Sonus Faber Stradivari and YG Acoustics Anat - both got "excellent" score. JBL K2 and Fostex RS2+NW3 got "much good" score, and Magico Mini and B&W 800D got "good" score. Other speakers did not get evaluation, since results disappointed.

I hope you do not think I am rude for correction. Also, I can say that for sound I am big fan of JBL and YG Acoustics - owned JBL K2 9800 in past, and now own YG Acoustics Kipod Studio.

Best lucky wishes,
Junichiro Tanaka

The Torus looks like an ideal bass complement for planar speakers.Anyone looking for depth and air displacement champ better look at JL and TC Sounds.

So what does the term infrasonic mean ?

Art

Art, i would'nt read too much into the "marketing" terms...i'm waiting on the TAS review of the Torus but judging by the charts i've seen, this "device" won't be linear below 20 Hz...remains to be seen just where it fits in the "scheme" of things...$9K is pretty stiff though...

It was painful to read through the marketing and techincal claims about this device in PDFs posted by Wilson-Benesch. They make some beautifully crafted hardware, but the claims on this one are way over the top to anyone who has a good understanding of how a cone-radiator loudspeaker operates. The device uses a unique motor design that appears to effectively be a ballanced/opposed VC/motor design that connects to the carbon-fiber cone pictured above. The end result is still movement of a cone with a big phase plug. I wouldn't be surprised if the motor is quite linear over some range of motion. It doesn't sound like that's a large range of motion.

Actually, "infrasonic" is the technically correct term for the range of frequencies lower than the audible human range (antonym: ultrasonic). The term "subsonic", although in common usage to describe the above, is incorrect in that role as it is the term for speeds lower than the speed of sound (antonym: supersonic). We call them subwoofers, of course, not "infrawoofers", but this is probably in reaction to "supertweeter" on the opposite end of the range.

But, anyway... the Torus seems to be a dual motor system driving a single diaphragm, much like an isobaric pair of woofers mounted face to face. This should result in linearity advantages, assuming the twin motors are dynamically consistent relative to each other. Despite the exotic motor architecture, it's still looks to me like a woofer, though.

I'm sorry, and not to offend anyone, but I just read through that PDF and it takes marketing jargon to a whole new level!!! At that price, for those output levels, it better come with 2 strippers, a bottle of 1984 Chateu Bourdeaux, and an all paid vacation to the greek isles.

$9500 ???

the Thigpen rotary looks like a bargain in comparison

...makes you wonder what's in store with the TAS review...

It's pretty.

Am I the only one with a subscription to TAS? I read the review last thursday. It doesnt sound like a true subwoofer, "only" an outstanding woofer. If you are looking for the punch and the extreme depth we all love, sounds like piston type drivers are still the way to go.

I guess with that being said, the reviews says it is reference grade bass (not sub-bass) reproduction.

More direct,and spot on.

Over $9000 for a deluxe MBM! Sorry,I but this thing is for a very very narrow sector of a very competitive market segment.

It is gorgeous,unique and built to world class standards...deluxe MBM style.It better be accurate and not a trace of bloat at this price.

In the end what do we know,it may match specific purist LF limited speakers in a way that no other device can.

seems so...the pdf download for this issue was'nt available last time i checked...

I have to admit to giggling to myself. Anyone ever hear of the Morel PP 300? It was a 12" dual motor "push-pull" woofer with a magnet, gap, & voice coil IN FRONT of the cone, and another identical set behind it. It used neo magnets, and looked like a woofer with a cylindrical "chunk" floating in front of the cone. I've searched the internet for pics, but I might have to dig through old spec sheets for something to scan. Let me know if there is interest...

The Wilson Benesch looks to be an impressively executed 18" version of that driver from almost 20 years ago now. The apparent lack of a spider and "control by the electronics" of dynamic recovery is something NEAR had a take on with the MLS:

http://www.soundstage.com/wrk_nr50.htm

I hope this puts perspective on "new" and "ground breaking". I think sometimes very clever and talented people that live somewhat apart from the rest of us get a really good idea, but don't do enough homework to sift through history on what has come before.

I admit to being curious what approach they are taking to centering. I've had musings about a DC offset to twin balanced coils, a kind of "servo center" that would be perturbed from center by desired bass drive signals. I'll be looking to hear one of these guys in the NW...



Martin

I stumbled across this and had to post a short response.

This development came out of a public supported research program that was fully audited in terms of expenditure and technical outcomes. To win such support in the first place is no small feat and in fact wilson Benesch is the only company in Europe that has acquired not one but several such grants. This is testimony to the fact that we are prepared to invest significant sums of money in real research and find innovative solutions to commonly accepted design problems. It also reflects our investment in manufacturing capability because to make the parts we design from aerospace materials requires science. These parts cannot be bought from anyone. Finally it should be known that a lot of clever people worked on this design and that the outcome is the result of collaborative work with people at the forefront of their industry and science.

Every detail of the Torus is original and has been granted a patent. During the patenting process which is very expensive, searches are done globally of all prior art in order to identify if the claims made are patentable.

The diaphragm alone is a considerable departure from anything done before by any company in the world and remains unique in construction and geometry. The function of push pull upon one diaphragm by two motors does not exist anywhere. The outer shell has no structural responsibility and is disassociated from the energy generating motors resulting in a total absence of cabinet noise in the outer ring. I could go on but this is already documented in the Torus manual that you can download should you wish to complete your homework.

Sorry the reply was so late.

By the way, for the company, the design is one of the most successful in terms of sales and happily resides in many systems from electrostatics to horns, in fact many systems where high performance transient response, low noise and a almost no overhang are seen as key to their sound.

A wonderful product to be sure, however, the Thigpen TRW-17 is in another league entirely as both pros like Tom Nousaine and member OTK can vouch for. Consider that the Thigpen is in the Guiness Book of World Records.

Kudos on your fine product