ok i just can't get enough bass.. Currently I am running 2 3015LF boxes from my last build which gets me about 129db from a meter away playing normal music.
I WANT 140DB.. I was looking at the BASSMAXX trip box idea as I have no issues with space.. 25x25 ft. living room with 20ft. ceilings..
I have a QSC 2450 for an amp.. Someone tell me if with this amp can I hit 140 db down to 40hz and maybe 135+ at 35hz..
Tell me what to build and buy.. I want to have to screw in the pictures on the wall.. Thanks for the help!!
I WANT 140DB.. I was looking at the BASSMAXX trip box idea as I have no issues with space.. 25x25 ft. living room with 20ft. ceilings..
I have a QSC 2450 for an amp.. Someone tell me if with this amp can I hit 140 db down to 40hz and maybe 135+ at 35hz..
Tell me what to build and buy.. I want to have to screw in the pictures on the wall.. Thanks for the help!!
I don't have a huge amount of experience with subs or very high SPLs, but from the sound of things you're best bet is probably using some very large 18-21" pro drivers, or alternatively building a bass horn or two. It's good that you're only aiming for 35-40hz too because that is actually a realistic goal I'd have thought.
Edit - can your mains actually keep up with this requirement? Or are you only after the insane SPL requirement in the bass? I hope this is only a goal you wish to achieve rather then regularly use otherwise you'll soon find yourself suffering from hearing loss.
Edit - can your mains actually keep up with this requirement? Or are you only after the insane SPL requirement in the bass? I hope this is only a goal you wish to achieve rather then regularly use otherwise you'll soon find yourself suffering from hearing loss.
Try a jet engine at ten meters.
The Straight Dope: Can a noise be loud enough to kill you?
Most impressive I ever experienced was from a rare set of Klipsh LaSals (sp?) driven with a real 80W RMS. Base drum thumps felt like shock of high powered rifle going off next to you on a rifle range. These were some sort of high end Klipsh speakers intended for use at large concerts. Never seen or heard of a set since. I recall them being like six feet wide and five feet tall... but that's just a guess.
Doc
The Straight Dope: Can a noise be loud enough to kill you?
Most impressive I ever experienced was from a rare set of Klipsh LaSals (sp?) driven with a real 80W RMS. Base drum thumps felt like shock of high powered rifle going off next to you on a rifle range. These were some sort of high end Klipsh speakers intended for use at large concerts. Never seen or heard of a set since. I recall them being like six feet wide and five feet tall... but that's just a guess.
Doc
i cannot have 8 TH boxes lined up across the living room.. anyone see this BASSMAXX X3 Trip box.. its only 4ft. x4ft. x 2ft.. and says it can hit 141 continuously.. any idea how to make something like this?? and yes my high's are the eon 15's which are good enuf for my living room not worried about excessive quality like in my theatre room.
You will need to displace 121,372 cubic centimeters of air to get 140db at 25hz.
And you will need 60,686 cubic centimeters of air for 140db at 35hz.
As well as 30,343 cubic centimeters of air for 140db at 50hz.
That should give you some idea of what it would take to reach such levels !!!
jer
And you will need 60,686 cubic centimeters of air for 140db at 35hz.
As well as 30,343 cubic centimeters of air for 140db at 50hz.
That should give you some idea of what it would take to reach such levels !!!
jer
You will need to displace 121,372 cubic centimeters of air to get 140db at 25hz.
And you will need 60,686 cubic centimeters of air for 140db at 35hz.
As well as 30,343 cubic centimeters of air for 140db at 50hz.
That should give you some idea of what it would take to reach such levels !!!
jer
Gee where do we start.... 30l at 50hz lets see - there are double 18" boxes that do 140dB and I'm sure the displacement is well under 2l. What about the Danley stuff that puts out ~150dB???
We just built 18 definite purpose boxes using 2x FaitalPro 18xl1500 at work. In a ~300L box with a single center vent and an f3 of 37Hz, we measured 146 @1M quarter loaded using pink with a lab fp3400 in bridged mode. That was at max output of the labgruppen and with headhoom to spare in the drivers. So, it's totally doable.
Well, If an 18" has a surface area of 254 with a excursion of 1" it would take 7.28 of them to do 50hz.
So 16 of them is about what I figured would get you to the 30hz range.
But that is at 1" excursion.
But if you concentrate the energy with a horn of some sort you may get some more gain out of them.
jer
So 16 of them is about what I figured would get you to the 30hz range.
But that is at 1" excursion.
But if you concentrate the energy with a horn of some sort you may get some more gain out of them.
jer
The way it works is that the SPL at a given frequency goes up 12 dB when you quadruple the displacement.
Let's try for 30 Hz-we can always back off down to 40 Hz if we need to.
At 30 Hz, 128 cu in gives us 117 dB.
So, 512 cu in gives us 129 dB.
So, 2048 cu in gives 141 dB.
That means that, using closed boxes, we would need the cone area times the displacement to equal 2048 cu inches.
Assuming a one inch throw on a PA speaker, that means a cone area in a closed box of 2048 square inches. Considering a 15 inch speaker has a cone area of 130 sq inches or so, that means you would need about sixteen 15 inchers to achieve 140 dB @30 Hz.
Let's try for 30 Hz-we can always back off down to 40 Hz if we need to.
At 30 Hz, 128 cu in gives us 117 dB.
So, 512 cu in gives us 129 dB.
So, 2048 cu in gives 141 dB.
That means that, using closed boxes, we would need the cone area times the displacement to equal 2048 cu inches.
Assuming a one inch throw on a PA speaker, that means a cone area in a closed box of 2048 square inches. Considering a 15 inch speaker has a cone area of 130 sq inches or so, that means you would need about sixteen 15 inchers to achieve 140 dB @30 Hz.
Assuming you don't want to do that, there are things you can do.
A. You can move your target frequency up to 40 Hz;
B. You can use ported enclosures, which change things in your favor.
Let's see what the displacement is for 140 dB at 40 Hz instead of 30 Hz. As we can see, 128 cu inches gives us 122 dB.
512 cu inches gives us 134 dB.
1024 cu inches gives us 140 dB. (Double the displacement = +6 dB).
Assuming a one inch travel on a PA speaker, that means 1024 sq inches, or about eight 15 inchers.
That is in a closed box.
However, if you use a vented box with a Qts of 0.38 or so, you can cut that displacement requirement by 4. Instead of a cone area of 1024 sq inches, (assuming a one inch throw on your PA speaker), you now need only one quarter as much, 256 sq inches. Since most 15's have a cone area around 130 sq inches, you should be able to get this done with two vented box 15 inch PA speakers, with a one inch throw, with a Qts around 0.38, a box volume equal to the speaker's Vas and tuned to 40 Hz or so.
A. You can move your target frequency up to 40 Hz;
B. You can use ported enclosures, which change things in your favor.
Let's see what the displacement is for 140 dB at 40 Hz instead of 30 Hz. As we can see, 128 cu inches gives us 122 dB.
512 cu inches gives us 134 dB.
1024 cu inches gives us 140 dB. (Double the displacement = +6 dB).
Assuming a one inch travel on a PA speaker, that means 1024 sq inches, or about eight 15 inchers.
That is in a closed box.
However, if you use a vented box with a Qts of 0.38 or so, you can cut that displacement requirement by 4. Instead of a cone area of 1024 sq inches, (assuming a one inch throw on your PA speaker), you now need only one quarter as much, 256 sq inches. Since most 15's have a cone area around 130 sq inches, you should be able to get this done with two vented box 15 inch PA speakers, with a one inch throw, with a Qts around 0.38, a box volume equal to the speaker's Vas and tuned to 40 Hz or so.
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