Replace jbl 2242

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Hi, i want to upgrade my 2.1 setup in the basement. I have a pair of diysg tempest 12 and a jbl 2242 in a ported box. My electronics are two crown xls1502 and a mini dsp 2x4 with dirac. I was thinking about replacing the jbl with a Dayton Audio pa 465s-8. Later mayby two. I simulated a 300liter and 25hz ported box, i think it gave a good response. I mainly listen to music. Is this a good idea or should i go for something else?
 
It does not go loud enough. It doesn't do so well in the low parts either. I was initially planning to go with the dayton audio UM18-22, but I don't think I got the power to keep up with the tempest sensitivity. I'm very open to suggestions though. I haven't made any decisions yet.
 
Loud with multiple subwoofers also means you need to configure them well. Especially when combining ported and sealed, not sure if that's the case. I use the multi sub optimizer software and would recommend everybody with multiple subs and at least moderate perseverance to do so as well :). You want something more advanced than Dirac.

Apart from inadequate phase overlap, the response and efficiency is also to a large extent determined by placement and resulting standing wave pattern. Trying to "correct" nulls in the response can cost lots of power and reduce headroom by a lot.

If you still need more output, I wouldn't move trrom a pro 18" to a more budget oriented 18" (I'm a huge Dayton fan BTW), but rather go for a pro 21" like the Hereford mentioned b&c ds115 or the new Eminence 21" which looks really good! A low tuned vented enclosure, or a higher order system if you can handle the building complexity and space requirement.
 
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Are you running a high pass filter on your sub? you could be wasting a lot of output on subsonics. The JBL driver in an appropriate ported box should be capable of massive >30Hz output. Whats running out of headroom the amp or the driver?

Also positioning could be important, you could be sitting in a bass null. I use four subs, spread around the room to smooth out the response. I never get anywhere near running them full power.
 
Personally I can't imagine that a single 18" with a bridged 1502 isn't cutting it. I would look deeper into your current setup to make sure everything is optimized at this point before spending money. Going for a driver with more Xmax (then 9 mm), requires a larger amplifier to utilize that extra excursion. Unless you tune it significantly lower. non of the mentioned 18" or 21" drivers will be substantially louder when driven with the same amplifier.

Can you give details on your current setup?

Johan
 
The details I can think of that i haven't told about is the cabinet for the jbl. I tried to copy the jbl box that they used the 2242 in. One mistake I made was I made the port rectangular instead of round. I thought that I could keep the area same and be safe, but I have heard that that's not the case. I feel like something is wrong with the sub. I have had louder 12" subs in the car :) maybe tuning? I have copied the box I built in winisd and I think it looks OK.
 
I feel like something is wrong with the sub
That would be my first guess, second the amplifier/ crossover settings and third the placement.

The 2242 has been used in a variety of enclosures, some of which were tuned rather high, so it might just not dig deep enough to get that "feel". If the port area is large enough a square port will be just fine. A 12" in a car will get massive gain due to the small space and sometimes also due to the resonance frequency of that space. Placement in general can have a large impact on the output of a sub, due to room nodes and phase around the crossover. To paraphrase jag: Trying to correct those nulls in the response can cost lots of power and reduce output by a lot.

Jag768 and kipman725 asked some good questions, to combine them with my own:

- How is the sub placed?
- Do you use a high pass?
- What are your crossover settings?
- Have you tried reversing the polarity on the sub?
- Can you tell us the internal volume and port dimensions of your current sub? (WinISD input would be nice).
 
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