If you need to go also low, IB installation using attic as backspace is one option. Then you need just 8 LMS-5400 with 30kW or 12 FI IB318 with 11 kW.
Simulation have 4'th order high pass at 15Hz to get more output without bottoming drivers below 20Hz. Room should add few db to low end.
Simulation have 4'th order high pass at 15Hz to get more output without bottoming drivers below 20Hz. Room should add few db to low end.
Attachments
This the the link to the spreadsheet I used to come up with my numbers.
In the past I have compared it's figures against other speaker design programs and is at least within 10% and/or better with the figures from winlsd.
So,Anyway, I trust it.
Yes you can get 140db at 50hz fairly easy,But as you go lower your displacement requirements go up drasticaly.
justint, Had specified 40hz so I was going for a lower frequency's of 25hz to 35hz as this would help to compensate for the extreme excursion and thus lowering the THD at 40hz at that level.
Although you may not hear the difference in the room, But, If the system was outside you would.
http://www.linkwitzlab.com/spl_max1.xls
jer
In the past I have compared it's figures against other speaker design programs and is at least within 10% and/or better with the figures from winlsd.
So,Anyway, I trust it.
Yes you can get 140db at 50hz fairly easy,But as you go lower your displacement requirements go up drasticaly.
justint, Had specified 40hz so I was going for a lower frequency's of 25hz to 35hz as this would help to compensate for the extreme excursion and thus lowering the THD at 40hz at that level.
Although you may not hear the difference in the room, But, If the system was outside you would.
http://www.linkwitzlab.com/spl_max1.xls
jer
we need a suitable design for Justin's 3015LF
If you can give him 140 dB @ 30Hz from a pair of them, I will be very impressed!
Regards, Ben
Not gonna happen ben... extension and spl are the two players on the see-saw (as you know)
justint built don's upandback TH that goes low(er), is small(er), and gives up some spl.
The ss15 wouldn't quite get there in pairs in a perfect corner... but it gets in the ballpark.
The tradeoff? no 35hz. Others have found 32hz 24db/oct butterworth high pass will let you get some under 40hz in a ss15 while keeping it safe within xmax bounds. The room will depend on how 'flat' it actually gets below Fc.
If you are a spl nut, and have others that live in the house with you.... I can't imagine bringing in anything bigger than a pair of ss15. It'll get you spl, you just have to give up the really really low notes.
Attachments
Here's the very, very easy way to do it:
Build a large sealed enclosure, say about 3x4x6 feet. Design it so that the back can hinge open and install a normal 12" subwoofer (Free air type?) in the baffle. Power with 100W, that's plenty.
Now here's the trick: to listen to the subwoofer, open the hatch, get inside, and lock it behind you. Inside the small "cabin" the SPLs will easily reach 140dB, and you will not cause any structural damage to your home although your hearing will likely be destroyed in only a couple of seconds.
This is why it is possible to launch those stupid SPL wars in a car, but not in a home. Duh.
-Charlie
Build a large sealed enclosure, say about 3x4x6 feet. Design it so that the back can hinge open and install a normal 12" subwoofer (Free air type?) in the baffle. Power with 100W, that's plenty.
Now here's the trick: to listen to the subwoofer, open the hatch, get inside, and lock it behind you. Inside the small "cabin" the SPLs will easily reach 140dB, and you will not cause any structural damage to your home although your hearing will likely be destroyed in only a couple of seconds.
This is why it is possible to launch those stupid SPL wars in a car, but not in a home. Duh.
-Charlie
Here's the thing...you can only use this capability without quickly deafening yourself if you use ear protection of the highest rating (34dB NRR) and even then you'll be exposed to a residual well past 100dB and unsafe for more than a short time. Furthermore, very high intensity low frequency sound will produce anxiety and nausea despite the ear protection due to direct effects on the body core. It's as though you asked folks on a blog how to kill yourself & many are chiming in with how best to tie a hangman's noose or how far into your mouth the barrel of the pistol should be inserted. If you just want to model how this might be accomplished as an exercise that's one thing...but if you plan to proceed my advice would be DON'T!
2 of these should get it with 3-4Kw worth of amplifier on each. Useable to 25Hz.
http://www.diyaudio.com/forums/subwoofers/193418-othorn-tapped-horn.html
Alternatively if you need power down to 15Hz 2 of these might pull it off.
http://www.diyaudio.com/forums/subwoofers/189784-gjallerhorn.html
I'd say go for it!
http://www.diyaudio.com/forums/subwoofers/193418-othorn-tapped-horn.html
Alternatively if you need power down to 15Hz 2 of these might pull it off.
http://www.diyaudio.com/forums/subwoofers/189784-gjallerhorn.html
I'd say go for it!
I think he's already partially deaf from the extreme SPLs he subjects himself to. Before I built a 140 dB sound system I'd get my ears checked just to know if I'm just accelerating my impending deafness.
BTW, what would be the point of achieving 140 dB and wearing 34 dB attenuators? Take off the protectors, turn it down 34dB and save a lot of money and annoyance of the neighbors.
G²
Even short term exposure is going to result in immediate and permanent hearing loss.
Even a slightly more reasonable 106 - 110dBspl at the listening position is brutally loud and will cause hearing loss in short order.
"You got me ticking gonna blow my top"
Top 10 Loudest Noises
#10 Rock Concert: 135-145 decibels
# 6 Space Shuttle Launch: 165-170 decibels
# 1 Tunguska Meteor: 300-315 decibels
.
Top 10 Loudest Noises
#10 Rock Concert: 135-145 decibels
# 6 Space Shuttle Launch: 165-170 decibels
An externally hosted image should be here but it was not working when we last tested it.
# 1 Tunguska Meteor: 300-315 decibels
.
these posts are awesome!! the knowledge is good.. regardless of hearing loss I am building this system.. I am not sure if I can go 4 double 15's or 18's because i don't want my house to look ridiculous when i have guests in the living room but here is what i will give up for space 7ft wide 7 feet tall and 3 feet deep.. What is the loudest I can get with that type of box space.. Oh by the way this is a corner area behind my 65" tv which is on a stand i can post picture if anyone needs.. currently you can't see my two TH 3015LF's which are behind the TV and stand 44" tall..
If you are going to make a sub system that will do 136db+ at 25Hz you will need to replace the glass in all the windows in your house with 1/4" Lexan. If you have neighbors within 50ft all the windows on the facing side of their house as well just in case you open a door or window while playing your system. The drywall will need to be replaced with plywood on rubber stud dampers.
Load up on guns, bring your friends
Oh, well, just put a 60" subwoofer behind it . . .
"The cone moves 6 inches peak to peak under full-tilt output."
"The woofer was designed with the capability to produce SPL levels of 188 dB."
.
Oh, well, just put a 60" subwoofer behind it . . .
An externally hosted image should be here but it was not working when we last tested it.
"The cone moves 6 inches peak to peak under full-tilt output."
"The woofer was designed with the capability to produce SPL levels of 188 dB."
.
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.