If I wanted a sub to do 5-20 hz at 125 db at 5 meters in a 8000cf room, how would I do this. I want clean output, I can eq the hell out of it to get a flat response, but I don't want to hear drivers moving etc. Thanks.
Budget is £60000.
Budget is £60000.
To do it with conventional drivers:
Assume 18 inch drivers with a 1/2 inch xmax.
You'll need 40 of them in sealed enclosures to reach 125.5 dB. You'll need more if your room is not nearly airtight and/or has flexible walls / floor / ceiling.
Assume 18 inch drivers with a 1/2 inch xmax.
You'll need 40 of them in sealed enclosures to reach 125.5 dB. You'll need more if your room is not nearly airtight and/or has flexible walls / floor / ceiling.
That rotary driver thing isn't clean! I would go with the Fostex 31.5" drivers if it were me and I simmed about 15 of then once with compromise got them to 3Hz although they do have very limited xmax.
May I ask what this would be for?
May I ask what this would be for?
My BFM THT with 2x15 Dayon DVCs flexes my walls pretty well at 5hz. Too bad I don't have a decibel meter, then I'd tell you what it's at.
Hi,
5Hz at 125dB at 5m not 1m ?, your having a laugh, that will
need a lot more than 3 of those rotary subwoofers, about 15.
However it might be able to be approached if you want 5Hz and only 5Hz via
some highly resonant arrangement with a dreadful frequency and transient
response, though you might need all of the next rooms volume to do it.
e.g. arranging the rear loading of the rotary drivers to resonate at 5Hz.
rgds, sreten.
5Hz at 125dB at 5m not 1m ?, your having a laugh, that will
need a lot more than 3 of those rotary subwoofers, about 15.
However it might be able to be approached if you want 5Hz and only 5Hz via
some highly resonant arrangement with a dreadful frequency and transient
response, though you might need all of the next rooms volume to do it.
e.g. arranging the rear loading of the rotary drivers to resonate at 5Hz.
rgds, sreten.
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I think you are in the wrong forum for 5Hz at 125 dB
Those devices are called "sonic boom generators" so call Thomas Danley at Danley Sound Labs and he can tell you if 60,000 pounds would do it. Tom built sonic boom generators before building speakers so he would be the man to ask.
Those devices are called "sonic boom generators" so call Thomas Danley at Danley Sound Labs and he can tell you if 60,000 pounds would do it. Tom built sonic boom generators before building speakers so he would be the man to ask.
When car audio nuts want to produce crazy SPLs in a van, they just use a whole bunch of woofers and amps, not exotic unconventional drivers. I suspect the solution will be to buy a truckload of woofers that offer excursion value for money and a lot of MDF and glue and start building a wall of sealed boxes in a manifold arrangement.
Hi,
😀 Suggestion: A wall of subs within the budget:Buy 72 TC Sounds LMS Ultra 5400 18" DVC Subwoofers
as the
Budget is = £60000 = 94326 US$,
Price per driver in UK = 925.99 + $70.99 Standard Shipping = 996,98....= 94 drivers at max....
Use 72 drivers in 36 x ~4.5m^3 TH's, when stacked 6x6 = ~162 cubic meters ..Available room volume=~226 cubic meters ~ The submitted Picture.
b 🙂
😀 Suggestion: A wall of subs within the budget:Buy 72 TC Sounds LMS Ultra 5400 18" DVC Subwoofers
as the
Budget is = £60000 = 94326 US$,
Price per driver in UK = 925.99 + $70.99 Standard Shipping = 996,98....= 94 drivers at max....
Use 72 drivers in 36 x ~4.5m^3 TH's, when stacked 6x6 = ~162 cubic meters ..Available room volume=~226 cubic meters ~ The submitted Picture.
b 🙂
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hmm 50Kw into the subs will need some serious amplifier. Also you must be joking your house will actualy fall down as your pumping massive energy in at the resonant frequancy of a typical brick house!
Lol, IMO one of these sub would generate unbearable SPL in a concrete wall room even at 1W input:
b 🙂
Attachments
Reason for this question...I just want to experience it. Going to use it in a much larger room later for dubstep. Some songs like firepower by datsik actually drop that low. Was hoping there would be an easier way of doing it like a few pd 24inch drivers in a horn or something...
Response below even 30 Hz costs dearly in size, weight and power demands.
For portable use, Josh Ricci’s Gjallerhorn is probably the best for what you want to do.
http://www.diyaudio.com/forums/subwoofers/189784-gjallerhorn.html
Josh Ricci’s Gjallerhorn at 2 meter, ground plane, outdoors measures:
10hz 90.2db
12.5hz 105.2db
16hz 118.3db
20hz 122db
25hz 124.9db
31.5hz 125.8db
40hz 128.4db
50hz 127.2db
63hz 130.2db
80hz 130.9db
100hz 131.1db
125hz 123.6db
Four cabinets could hit around 124 dB at 16 Hz at four meters outside. Indoors, in a corner, they would do that level down to a lower frequency.
Then again, that is not even close to the output of the Matterhorn, a 40-driver, 40 kW self-powered Tom Danley designed tapped horn subwoofer which can produce 105 dB of output at 250 meters, with a response -3 dB at 12 Hz.
That is about 153 dB at one meter, 140 dB at 4 meters, 123 at 31 meters outdoors.
Matterhorn
Dat's sick, mon.
Art
Theoretically speaking, you could have all the king's horses and all the king's men fart at once (which is, strictly speaking, DC) but you'll be needin' a higher budget.
If you just want to experience it:
- Build an enclosure large enough to sit in, say 3 feet wide x 5 feet high x 6 feet long (90 cubic feet).
- Cut a hole in the end and screw on a single 15 inch driver, assuming xmax is at least 1/2 inch.
- Add a couple of small speakers to handle the rest of the frequency range.
- Climb in. Seal the door. Play your music.
- Build an enclosure large enough to sit in, say 3 feet wide x 5 feet high x 6 feet long (90 cubic feet).
- Cut a hole in the end and screw on a single 15 inch driver, assuming xmax is at least 1/2 inch.
- Add a couple of small speakers to handle the rest of the frequency range.
- Climb in. Seal the door. Play your music.
A reasonable car system with a sealed box sub should generate substantial output into the single digits. The electronics (source, crossover, amp) may have some high-pass filtering, though. Might be best using S/PDIF from the source (computer, CD, DVD, media player) and then a DAC or surround processor so there's only one analog link to worry about. Looking at the specs of a couple of amps, they claim -3dB down at 10 Hz or 20 Hz.
If you want to figure out what is a worthwhile low-end response, set up a wide range car system, then use a variable high-pass filter to see what is really necessary. Or just use a good spectrum analyzer on the music you like. I suspect that most of what you'll find below 20 Hz is air-conditioning noise, traffic rumbles, and some unwanted contributions of effects units or synth LFOs. The vast majority of studios aren't equipped to play back such low frequencies. To mix Black Hawk Down, which contains significant 7 Hz bass, the studio had to bring in 22 (don't know what size) Bag End subwoofers. (This does kind of beg the question: why? Is there a cinema anywhere that can reproduce 7 Hz? How many home theaters? Was it simply an admirable attempt to capture the sonic reality of the situation, but if they wanted accuracy, shouldn't they also record gunfire and explosions with the appropriate dynamic range?)
Regarding the "brown note". I don't think Mythbusters test was reasonable since they did it in free air with subs which must have had negligible response down that low. Is anyone aware of a more credible test (published, or Youtubed)?
If you want to figure out what is a worthwhile low-end response, set up a wide range car system, then use a variable high-pass filter to see what is really necessary. Or just use a good spectrum analyzer on the music you like. I suspect that most of what you'll find below 20 Hz is air-conditioning noise, traffic rumbles, and some unwanted contributions of effects units or synth LFOs. The vast majority of studios aren't equipped to play back such low frequencies. To mix Black Hawk Down, which contains significant 7 Hz bass, the studio had to bring in 22 (don't know what size) Bag End subwoofers. (This does kind of beg the question: why? Is there a cinema anywhere that can reproduce 7 Hz? How many home theaters? Was it simply an admirable attempt to capture the sonic reality of the situation, but if they wanted accuracy, shouldn't they also record gunfire and explosions with the appropriate dynamic range?)
Regarding the "brown note". I don't think Mythbusters test was reasonable since they did it in free air with subs which must have had negligible response down that low. Is anyone aware of a more credible test (published, or Youtubed)?
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