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View Full Version : Which 18 ?



Tom Loizeaux
03-18-2005, 07:18 PM
Though I like the JBL 2242H for a number of reasons, I am wondering if there might be a better 18" driver for my application.
I have an 8 cu.ft. cabinet that I want to use as a "helper" low end cabinet in a small PA system. The mains are two pairs of JBL K140s in cabinets tuned around 40Hz. They sound fine for the low end, but I want to be able to add a little extra low end in some events (outdoors, especially) without simply pushing the 15s by pushing up the low end EQ. My 3 way crossover has a seperate "Sub Out", so I can drive my sub while still giving my 15s everything below their transition to mids.
The 2242H has a gentle roll off starting about 150Hz and is down about 5 dB by 40Hz in an enclosure tuned to 32Hz. The Gauss 4883B, for comparison, is flat from 250 down to 30Hz! It only shows a sensitivity of 96dB, but it doesn't have the big peak the 2242 has between 1K and 2K, which may account for some of the JBL's 99dB sensitivity. I don't plan to use this "Sub" above 200Hz.
The Gauss in this example does require a larger cabinet (10 cu.ft.) and a port of 45 sq. in. with a 10" duct.
My question is if there are other 18s that produce deep low end in medium cabinets that I should consider over the 2242H.

Thanks for your opinions.

Tom

LE15-Thumper
03-18-2005, 08:30 PM
How about the 2245 ? Or even a set of 2235's :dont-know....smaller box

dieterj
03-19-2005, 04:04 AM
I would go with a couple of 2242 in double Enclosure :D

arrgh5
03-19-2005, 12:14 PM
http://www.jblpro.com/ae/asb6128v.html


Too big, too expensive but 3 dB at 25 Hz 300 Hz ! :D and cont. avg. spl is
134 dB between 30 Hz 100 Hz. :applaud:

Tom Loizeaux
03-31-2005, 07:56 AM
Any more opinions on other 18" drivers, like Gauss, for my sub woofer application?

Tom

arrgh5
03-31-2005, 08:44 AM
http://www.jblpro.com/srx700/PDF/JBL.SRX718S.pdf

3 dB at 34 Hz 220 Hz , 36 Kg:applaud: , 95 db 1w/1m :( .

Better ?

Btw, i got two of these

http://www.jblpro.com/srx700/PDF/JBL.SRX728S.pdf

to support the old sr4715s at the low end.:D

Earl K
03-31-2005, 10:02 AM
Hi Tom,

- For live work , you should be thinking of at least a pair of 18(s) / not a single . This is even truer for any outdoors work where more than 2 is better since the outdoors lacks the typical "boundry effects" that help woofers be louder in doors .

- I'd recommend a pair of 2245H(s) in 8 cu' boxes tuned higher .
Something like 35hz. If I remember correctly this gives a quasi box-box alignment. Very , very nice woof comes out of this setup . A friend of mine uses twin 2245h(s) as subs for small AV events. This setup works really well for him and these woofers never seems to need any EQ to make sound "correct" .

- The upshot to getting 2245H woofers , is that you can eventually use them at home .

- If you don't want foam surrounds on your gigs then look for a woofer with linen surrounds with the following characteristics : 30 to 35 hz Fs, a Qts of at least .33 or lower / an mms figure of 185grams or higher / an Xmax of at least 9mm, efficiency of 95db or more, and a power handling of at least 600 watts .

- the above criteria will narrow the field quite a lot .


:cheers:

4313B
03-31-2005, 10:26 AM
Though I like the JBL 2242H for a number of reasons, I am wondering if there might be a better 18" driver for my application.
I have an 8 cu.ft. cabinet that I want to use as a "helper" low end cabinet in a small PA system. The mains are two pairs of JBL K140s in cabinets tuned around 40Hz. They sound fine for the low end, but I want to be able to add a little extra low end in some events (outdoors, especially) without simply pushing the 15s by pushing up the low end EQ. My 3 way crossover has a seperate "Sub Out", so I can drive my sub while still giving my 15s everything below their transition to mids.
The 2242H has a gentle roll off starting about 150Hz and is down about 5 dB by 40Hz in an enclosure tuned to 32Hz. The Gauss 4883B, for comparison, is flat from 250 down to 30Hz! It only shows a sensitivity of 96dB, but it doesn't have the big peak the 2242 has between 1K and 2K, which may account for some of the JBL's 99dB sensitivity. I don't plan to use this "Sub" above 200Hz.
The Gauss in this example does require a larger cabinet (10 cu.ft.) and a port of 45 sq. in. with a 10" duct.
My question is if there are other 18s that produce deep low end in medium cabinets that I should consider over the 2242H.

Thanks for your opinions.

TomCompare the Gauss 4883B directly with the 2245H.

Keep in mind your low pass filter.

The 4883B "likes" a volume of ~ 8 to 16 cu ft while the 2242H "likes" a significantly smaller volume.

Here's an example of the 2242H and 4883B in a 4645C enclosure coupled with a LR 80 Hz LP filter.