18" subwoofer

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Rubycon

Madame President
Aug 10, 2005
17,768
485
126
Originally posted by: Viperoni
The Mad cabinet probably has nothing below 35hz without heavy equalization, in fact:

Frequency Response: 20Hz-100Hz, +/- 3dB, Equalized

The driver can handle it though.

Best bet for going super deep in an HT would be the largest and highest excursion TC sounds driver, like one that Howard suggested.
This thing is insane: http://www.tcsounds.com/lms5400.htm

That looks more like something that would go in a trophy auto sound system - not for hard continuous pro use.

A LOT of sealed boxes will use EQ to get down to a solid 20Hz. It does need amp power which is really cheap these days.

This looks pretty nasty. :evil:

EDIT: Wow only $7k. :Q
 

imported_Baloo

Golden Member
Feb 2, 2006
1,782
0
0
That long excursion is gonna introduce a lot of distortion. If accuracy, of fidelity, is important, go with a much lower excursion, the lower the better.
 

Viperoni

Lifer
Jan 4, 2000
11,084
1
71
Originally posted by: Rubycon
Originally posted by: Viperoni
The Mad cabinet probably has nothing below 35hz without heavy equalization, in fact:

Frequency Response: 20Hz-100Hz, +/- 3dB, Equalized

The driver can handle it though.

Best bet for going super deep in an HT would be the largest and highest excursion TC sounds driver, like one that Howard suggested.
This thing is insane: http://www.tcsounds.com/lms5400.htm

That looks more like something that would go in a trophy auto sound system - not for hard continuous pro use.

A LOT of sealed boxes will use EQ to get down to a solid 20Hz. It does need amp power which is really cheap these days.

This looks pretty nasty. :evil:

EDIT: Wow only $7k. :Q


Looks can be deceiving. That is probably one of the best choices for getting ridiculously loud at ridiculously low frequencies.

And if you want to talk about "pro sound calibre" , I have a pair of 18" Mach5Audio MJ18's in 3.25cf sealed each, that withstood 1200 watts RMS a piece from a Yorkville AP4.4 amp, at clipping, for over an hour, on music.
They only have 3" coils and are only rated for 600 watts RMS.


Assuming the TC Sounds driver wouldn't go into overexcursion, I wouldn't worry about plugging it directly into a wall outlet just for kicks. I have a TC Sounds based driver, and they're TANKS.
 

Adul

Elite Member
Oct 9, 1999
32,999
44
91
danny.tangtam.com
Originally posted by: Minerva
13" though. :(

Sounds like car audio stuff. Pro sound will rape the car toys. I need a driver that rocks to 20Hz that can blow a rat across the floor.

you dont know anything about JL Audio then.


Just look up the avs forums and read the giant Fathom F113 sub thread.
Its getting some rave reviews and really delivers. Its driver is based on the JL audio W7 driver. Except with a boat load more power on it. 2500 watts.
 

Howard

Lifer
Oct 14, 1999
47,982
11
81
Bass horns are superior (no super-low-efficiency drivers like the LMS-5400 necessary) when it comes to high SPL reproduction. Not so good at space efficiency, but you can't have everything.
 

Rubycon

Madame President
Aug 10, 2005
17,768
485
126
Originally posted by: Howard

What exactly is pro sound caliber?

Anything that can perform day after day without losing its character sound. LOUD and CLEAR with sufficient headroom to make people run if needed. :evil:

Originally posted by: Viperoni


Looks can be deceiving. That is probably one of the best choices for getting ridiculously loud at ridiculously low frequencies.

And if you want to talk about "pro sound calibre" , I have a pair of 18" Mach5Audio MJ18's in 3.25cf sealed each, that withstood 1200 watts RMS a piece from a Yorkville AP4.4 amp, at clipping, for over an hour, on music.
They only have 3" coils and are only rated for 600 watts RMS.


Assuming the TC Sounds driver wouldn't go into overexcursion, I wouldn't worry about plugging it directly into a wall outlet just for kicks. I have a TC Sounds based driver, and they're TANKS.

A 120VAC outlet has 60Hz at 1875W available assuming the impedance is low enough at 60Hz to draw that. And if it is, the voice coil will heat excessively increasing the impedance - a victim of power compression. If the driver is relatively unloaded and the excursion is high enough to pump sufficient air throughout the gap the coil could stay decently cool. Either way it's a fun experiment. :) Most "hyper" drivers have progressive suspensions with extremely tight restraints to prevent them from getting out of control - a shorting ring affords that extra protection in case there's no low cut and a dj drops the needle from way up. :Q


Originally posted by: Adul
Originally posted by: Minerva
13" though. :(

Sounds like car audio stuff. Pro sound will rape the car toys. I need a driver that rocks to 20Hz that can blow a rat across the floor.

you dont know anything about JL Audio then.


Just look up the avs forums and read the giant Fathom F113 sub thread.
Its getting some rave reviews and really delivers. Its driver is based on the JL audio W7 driver. Except with a boat load more power on it. 2500 watts.

There is no replacement for displacement. I guarantee you she knows that much being a gear head. :Q JL is not pro stuff. Heck look at the manufacture's warranty. If it's used for reinforcement (PA etc.) warranty VOID. Why do you think that is? As a performer/engineer I can tell you we push equipment to the MAX. Good stuff stays clean until people cry uncle. :) A boxie that roars 160 dB in a hatchback is barely going to be heard at the back of our 1000 seat theatre.

Originally posted by: Howard
Bass horns are superior (no super-low-efficiency drivers like the LMS-5400 necessary) when it comes to high SPL reproduction. Not so good at space efficiency, but you can't have everything.

Sure but why stop at 12"?

Getting back to the OP -

You know you can take care of pesky vermin with a strong tank (1" thick steel will work), a neon sign transformer, spark plugs and acetylene tank. Get the right mixture and it will go BOOM with the report of an 8" howitzer spewing several yards of bright orange flame out the end. That rat will sail like St Judy's Comet with a trail of something. (the pressure isn't high enough to turn rat poop into diamonds but you will get something.)
 

sdifox

No Lifer
Sep 30, 2005
100,905
18,092
126
Originally posted by: Rubycon

You know you can take care of pesky vermin with a strong tank (1" thick steel will work), a neon sign transformer, spark plugs and acetylene tank. Get the right mixture and it will go BOOM with the report of an 8" howitzer spewing several yards of bright orange flame out the end. That rat will sail like St Judy's Comet with a trail of something. (the pressure isn't high enough to turn rat poop into diamonds but you will get something.)

OMG, I am laughing so hard... You are my heroine!
 

Howard

Lifer
Oct 14, 1999
47,982
11
81
Originally posted by: Rubycon
Originally posted by: Howard

What exactly is pro sound caliber?

Anything that can perform day after day without losing its character sound. LOUD and CLEAR with sufficient headroom to make people run if needed. :evil:
So why isn't that pro caliber?
Originally posted by: Rubycon
Originally posted by: Howard
Bass horns are superior (no super-low-efficiency drivers like the LMS-5400 necessary) when it comes to high SPL reproduction. Not so good at space efficiency, but you can't have everything.

Sure but why stop at 12"?
AFAIK, the output of a horn is generally limited by the thermal, not the excursive, capabilities of the driver. If you really want to know, play around with Hornresp. You may find that larger isn't always better.
 

GregGreen

Golden Member
Dec 5, 2000
1,688
5
81
swerving in the excursion limited
four eighteens two amps -- don't know what my limit is
 
Sep 29, 2004
18,656
68
91
BTW: excursion implies peak to peak .... the peak to peak jsut confuses people that kno what excursion is.
 

Rubycon

Madame President
Aug 10, 2005
17,768
485
126
The other aspect of pro sound - and probably the most important is field availability. Drivers - even the finest - do go bad, blow out (accidents always happen hehe) and nothing is more aggravating than not being able to remedy this in short order. The show must go on...

Most pro woofers can be field stripped and parts replaced and up an running in minutes. Ditto for compression drivers for mid and hi sections. Of course in theater most of the MF and HF sections are flying high in the air making access difficult in short order. A quick fix is the Poly Switch from Raychem. This is a self resetting fuse. I don't like their affect on the sound as they falsely intervene on lots of passages due to impedance shift however if a higher value Poly Switch is used which will intervene only with a serious continuous condition and a light bulb is used the rest of the time - a sonically acceptable protection circuit is established that keeps the mids and tweets singing faithfully. The incandescent bulb works quite well because its filament has an extremely low resistance when cold - as it heats up the resistance increases so the extra power heats the filament instead of the voice coils. It works well and lots of PA cabinets have them - as a matter of fact they use the popular 1156 tail lamp bulb so if it blows out from n00b jocks it can be field replaced easily. :)

BTW the purpose of reflex loading is to increase pressure on the cone at the tuning frequency and reduce excursion - the air inside the vent is essentially the radiator. Lots of excursion is good for sealed systems that beg for EQ to get down lower and it affords higher outputs on IB systems that run unloaded which can be disastrous to some suspension designs.

I'm sure with a sufficient amp and one of these jackhammer style woofs mounted in the floor, you could splat the rat on your ceiling if you get him on the dust cap and play a cannon shot at 0 dB into that thing.

If you are looking for a target SPL use this formula:

SPL = 112 + 10 log ( 4 * pi^3 * Ro / c * (num * Vd)^2 * f^4)
Vd = (.83 diam)^2 * pi / 4 * Xmax
solve for Xmax:
Xmax = srqt ( 10^((SPL - 112)/10) / (pi^5 * Ro / 4 / c * num^2 * (.83 * diam * f)^4) )
 

Howard

Lifer
Oct 14, 1999
47,982
11
81
Originally posted by: IHateMyJob2004
BTW: excursion implies peak to peak .... the peak to peak jsut confuses people that kno what excursion is.
Xmax should be defined one-way.
 

Tiamat

Lifer
Nov 25, 2003
14,068
5
71
Originally posted by: Minerva
13" though. :(

Sounds like car audio stuff. Pro sound will rape the car toys. I need a driver that rocks to 20Hz that can blow a rat across the floor.

Its not car audio. JL happens to also make one of the best HT/music sealed subwoofers as well. Subjectively its better than the Velodyne DD-18, objectively it is better as well. (Also better than my ACI Maestro XL). If you are limited to "normal" subwoofer sizes, these three are where its at. If you have unlimited desire for bass with no compromise, then that opens up doors.

Pro sound will have higher power handling because they are meant to deliver in vast spaces. But for sound quality, pro sound will not be better on a general scale (the typical stuff you can get for pro sound). The huge exception to what i just said is anything take comes out of Danley labs for sure. The DTS-20 or BDEAPs for example are very applicable for Home theater applications and even musical bass. For DIY, there are plenty of nice subs, TC Sounds, Avalanche (if you can find the 18), ...
 

patentman

Golden Member
Apr 8, 2005
1,035
1
0
Originally posted by: Goosemaster
Originally posted by: Minerva
13" though. :(

Sounds like car audio stuff. Pro sound will rape the car toys. I need a driver that rocks to 20Hz that can blow a rat across the floor.

I usually feed them potassium soaked in oil with a little cheese mixed in and then spray them with the hose.

good stuff.

Just wear safety goggles when doing that... ;)