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Author Topic: Amazing new Sub-Subwoofer Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 10-03-2005 09:14 PM                     Many of you may laugh at this idea but it really works. Upscale this thing to a larger unit and it would be amazing in cinemas! It would also blow the dust back out of the screen keeping the perfs open at all times . Here is a description of how it works.... now who woulda thought of this????? "This Eminent Technology unit that produces 110 dB at 10 Hz. It is designed to supplement subwoofers (!!!) in the 5 Hz to 20 Hz range. A 1/3 horse power motor turns the fan blades, which are connected to a rod in the center of a woofer voice coil. Instead of the voice coil moving a cone, it moves the rod, which then moves smaller rods that adjust the pitch of the fan blades. So, the high velocity air coming from the fan is pulsed at the low frequencies. It only takes about 100 watts of amplifier power to drive it. The entire room shook, and the door was opening and closing in time with the signal. All this, and there was almost no distortion (the ET rep had the response being plotted on a spectrum analyzer during the demonstration). They calculated that it would take ten 18" subwoofers to produce this level of sound. It has to be placed in a separate room due to the fan noise, and putting it in the attic would work fine. The opening into your home theater would be about 2'x4' in the ceiling. These are prototypes at this point." Here is a link to the manufacturers web site.....  |  IP: Logged David Stambaugh Film God Posts: 4021 From: Eugene, Oregon Registered: Jan 2002 posted 10-03-2005 11:16 PM                        Whoa! Andy Summers will go bonkers over that! Can any current cinema-grade digital audio system (SR-D, DTS, SDDS) actually reproduce frequencies in the range of 5-20Hz? (When I was into high-end audio, I had an Eminent Technology air-bearing tonearm on my VPI turntable. What a beautiful piece of engineering that tonearm was! The aquarium airhose snaking through the room to the isolated Silent Giant pump was an inconvenience, but hey, whatever it takes to extract every nuance out of those vinyl discs! )  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 10-03-2005 11:24 PM                     I could certainly envision a 15 foot diameter "Cinema Version" of that thing . Another round of Sensurround movies please... anything to get people back to the cinema! Mark  |  IP: Logged Paul Mayer Oh get out of it Melvin, before it pulls you under! Posts: 3836 From: Albuquerque, NM Registered: Feb 2000 posted 10-03-2005 11:40 PM                        I'll take two! I too am a happy owner of an Eminent Technology ET-II air bearing tonearm. Still have it mounted on the Sonograph. Dynavector 17DS, Shure V15MR, and Promethean Green cartridges. Sadly none of that stuff has been used in years, yet I can't bring myself to sell or dump it. One can never have too much low end response.  |  IP: Logged Frank Angel Film God Posts: 5305 From: Brooklyn NY USA Registered: Dec 1999 posted 10-04-2005 04:20 AM                        Three problems: 1)isolating the fan noise from the audio. If you can hear the audio, no matter if it is coming out of a hole in the wall with the unit placed in another room, how is it that you don't hear the fan noise? 2)Although there may very well be audio components below 20hz that are picked up by microphones (I contend that is mostly unwanted sound, like physical vibrations in the floor as well as air movement, etc -- stuff you DON'T want to hear), no one hears these rumbling sounds when listening to conventional playback systems, most importantly, not the sound mixing engineers in the mixing studio. So by adding a really significant amount of that ultra low frequency information to the playback -- information that the mixing engineer never heard when he was mixing the soundtrack -- you are throwing off the balance of the original mix, in my estimation, probably quite significantly. Additionally, this ultra subwoofer won't be able to distinguish between the movement of the musicians feet or structural vibrations of the building itself or the air turbulance in the recording studio and the music that is recorded. It won't just enhance ONLY the explosion, it will add lots of unwanted low-end noise along with it. 3) I would also be concerned about the effect of the ultra low frequency on upper frequencies. One of the problems with Sensurround was that the low frequencies would beat against the upper frequencies, especially in the voice range. Dialogue would sound like you were hearing voices through....oh, how conincidental....a fan. The low frequencies would cause a kind of mini-dopler effect on the higher frequences as it changed the density of the air that those frequencies had to traverce to get to the listener. Speak in front of a fan an you can hear that fluttering sound that the voice takes on. Maybe ten or fifteen years ago I recall seeing a subwoofer that was designed using a motor in conjunction with a driver, but I don't remember who manufactured it or what exactly was the design, other than its advantage was it could produce a very big sound from a small enclosure. There was no fan. Air cushioned tone arms....phooy! You want to talk about esoteric tonearms and turntables? -- how bout a player where NOTHING touches the LP -- nothing mechanical at all! . This baby uses a laser to read the audio in the grooves! Nothing touches the record except light. Check it out here: ELP Laser Turntable They are basically hand made in Japan as you order them and they cost about as much as a new Toyota Corolla, but damn they are sweet. I got their demo CD and the sound they are able to get from worn and even scratched LPs is amazing. Because the laser focuses at the lower portion of the groove, below where the needle usually rides, it misses all that inner groove distortion that was cause by mechanical needle wear at the top of the groove. Now if I can only convince the lady to let me buy a $15,000 toy....  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 10-04-2005 08:27 AM                     quote: Paul Mayer I too am a happy owner of an Eminent Technology ET-II air bearing tonearm. Still have it mounted on the Sonograph. Dynavector 17DS, Shure V15MR, and Promethean Green cartridges. Sadly none of that stuff has been used in years, yet I can't bring myself to sell or dump it. Paul, Next time I'm in Vegas, or St. George I'd like to get together and purchase that TT of yours so it doesn't end up in the dump!! One of my bad mistakes was selling my VPI and ET arm. The ET arm is one of the few arms of its type that really works..... quote: Frank Angel Three problems: 1)isolating the fan noise from the audio. If you can hear the audio, no matter if it is coming out of a hole in the wall with the unit placed in another room, how is it that you don't hear the fan noise? Apparently the fan turns at a slower rate so air flow is not a problem to mask..... check out movie of how it works on their site. The whole idea is to generate subsonics... something thats never been easy to do. I don't recall any dialog problems with Sensurround in the theatres in Chicago that I heard it in.... just plaster comming down!! The laser TT has many problems including a really bad manufacturer with a history of bad customer service and poor delivery. There is also a huge problem with it picking up dust on records played back. You have to clean amy record played back in the thing on a special 2,000.00 record cleaner. Smart was the forst US distributer but Norm gane up on the company. Mark  |  IP: Logged Louis Bornwasser Film God Posts: 4441 From: prospect ky usa Registered: Mar 2005 posted 10-04-2005 09:34 AM                        While we can argue that there may or may not be anything worthwhile at extreme L.F.; there is no difficulty recording it. Optical will reproduce "changes in atmospheric pressure" (Tom Holman). Digital should have no problem with 1 hz up until it converts to analog. Anything magnetic will have a difficulty. Louis  |  IP: Logged Frank Angel Film God Posts: 5305 From: Brooklyn NY USA Registered: Dec 1999 posted 10-04-2005 09:47 AM                        That's good to know, Mark, I was actually contemplating buying that EL LP player once when the company had a sale -- they had a few going for $6k, but even then it would have started a war in my household. It seems like a good design in theory. I guess what they need is for a big outfit like Panasonic or Sony to make them at a fair price. Reading the grooves using an optical system isn't the hard part, it's getting a mechanism that will track that groove that seems to be the major accomplishment. I corresponded with the CED and explained that if that unit was to find acceptance with the nitch market of audiophiles who still have LPs, he should really look into a financing plan that the company itself would manage or link up with some bank and offer financing thru the bank. Or of course figure out a way to make it cheaper. Interestingly enough, I saw EARTHQUAKE in a Chicago theatre, but I can't remember its name; I only recall is that it was a movie palace and it had it's entrance right on a street corner with doors facing both of the cross streets; it was maybe only a block or so from the EL. As it was told to me, that sound anomoly only happened in certain configurations of where the Cerwin Vega speaker bins were placed in a certain way. It was a fairly unpredictable combination of the room acoustics coupling and just bad luck. I don't recall any particular sound problems when I saw it in Chicago, but it was rather pronounced when I saw it again in Brooklyn in the Century Avalon theatre. The projectionist there told me they had some guys from Universal come in to try to fix it and they got it a little better my moving some of the side bins, but it never totally eliminated the problem. Luckily during the earthquake scenes no one was talking much, but the screams had that fluttery sound to them.  |  IP: Logged John McConnel Expert Film Handler Posts: 118 From: Okmulgee, OK USA Registered: Nov 2003 posted 10-04-2005 08:37 PM                        Could the theatre in Chicago have been the McVickers?  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 10-04-2005 09:52 PM                     There wass a review in either Absolute Sound or Stereofool on the elaser player. They liked it except for the noise issue. Recording subsonics is easy and Altec maDe mics that are flat down to the 5 hz region and can tolerate 145 db spl! These were mics made post WW-2. It could have been either McVickers or the United Artists Theatre. The UA was on a corner neaar the EL, so was the Chicago Theatre. I do remember seeing Midway at the Plitt Oakbrook Theatre. Mark  |  IP: Logged Aaron Sisemore Flaming Ribs beat Reeses Peanut Butter Cups any day! Posts: 3061 From: Rockwall TX USA Registered: Sep 1999 posted 10-04-2005 10:05 PM                     FWIW, the ELP laser turntable has some major drawbacks in comparison to a standard stylus-and-cartridge transducer: 1. it is EXTREMELY intolerant of dirty or scratched records. Even tiny (read: invisible) dust particles and scratches will cause it to mistrack horribly... 2. You cannot play anything but black vinyl records. No colored or clear vinyl. (like that matters with some people) Great idea but not yet ready for the majors... -Aaron  |  IP: Logged Josh Jones Redhat Posts: 1207 From: Plano, TX Registered: Apr 2000 posted 10-12-2005 01:42 PM                        I would tend to think that some of the fluttering you may have heard is probably your ears going into soft compression. ears, like mics are physical devices and have their limits. I would summize that our ears just run out of headroom when subjected to these high SPL's JJ  |  IP: Logged Andy Summers Master Film Handler Posts: 397 From: Bournemouth Dorset United kingdom Registered: Jun 2005 posted 10-14-2005 05:49 PM                 Mark’ Now I have had the same thought, yes a fan, I’m a big fan of sub bass, I like my JBL 4645 modified “THX” but this is a gem how much does it cost? The more of these units that are installed into the installation will increase the (SPL db fan level) wow, I cant access the web page, I’ve felt some wicked THX presentation sound at the “UCI” High Wycombe 6 many years ago, wicked…. Anyway post a complete schematics diagram for all to see, and doe’s anyone hear have any pictures of the THX 3417 crossover monitor, with the front cover taken off.  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 10-15-2005 08:31 AM                     Andy, It might be a good thing that you can't access that web site!! Its only 13K each. Mark  |  IP: Logged Andy Summers Master Film Handler Posts: 397 From: Bournemouth Dorset United kingdom Registered: Jun 2005 posted 10-15-2005 12:26 PM                 Mark’ Oh well plan “B” I well be patient, still looking at this (sub bass fan) is fascinating, is there any other angles of this (sub bass fan) unit to look at…. Fascinating… Mark’ Oh well plan “B” I well be patient, still looking at this (sub bass fan) is fascinating, is there any other angles of this (sub bass fan) unit to look at…. Fascinating… http://temp.corvetteforum.net/bss/nomad/spock_fascinating2.jpg  |  IP: Logged

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