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I've got a pair of these, brand new, all original, sitting in their original boxes, never been powered.

I previously owned a pair which came in a 2 x 15 cabinet for "fixed sub" applications for club or movie theater/commercial applications..

The sub/cabinet combo is model number 4648A, I've attached a link, the following link is for the 2 x 15 4648A cabinet I own which is loaded with the same pair of JBLs that I own (single 8 ohm voice coils each) I've included the link to the 2 x 15 cab which is loaded with these speakers, I've also included the T/S parameters for the individual drivers (I have the 8 ohm version, specs read accordingly)

https://www.jblpro.com/ProductAttachments/4648a.pdf

It is essentially a medium to largish front loaded bass reflex style 2 x 15 (depending on how you look at it.. it's a monolith of a cabinet for home theater, tiny for commercial use)

These are T/S parameters from JBLs site, these are for the individual 8 ohm version of each 15 that I have..

What I'd like to know is, how low can I get these to perform in a minivan? (Dodge Grand Caravan SE, third row seating already tossed to the curb)

Please check the specs in the PDF link.. The 2 x 15 JBL cab is
39 in x 25½ in x 17¾ box is tuned to 40hz, so they're showing a -10dB drop in the 30 hz range with that cabinet..

Now, is there anyway to get clean, solid sub 30hz performance out of these drivers with their limited excursion? Dare I ask if 20hz performance with near linear response to 80hz with massive output is out of the question?

I haven't used BassBox or any of these box programs for the longest and quite frankly, I don't remember how to use them. As for enclosure size, well, let's just say I have plenty of room.. I can go approx 55 x 65 x 24 (tall) give or take, as I mentioned earlier, I've already tossed the third row seating to the curb..

Here's another odd idea.. Since I am looking to work with what I have, am looking to put together an SQL system, must image well and have linear response with massive output, however, I'm not looking to compete or win trophies..

Again, looking to work with what I have, how about adding a pair of JBL W12GTIs for true subs, the JBL 2226HPLs for midbass, and then figure out what to do for highs?

I have a Pioneer 80PRS,
I have the JBL 2x15 cab,
I've also got a massive 2 x 12 cab for the GTIs, all fill fit snugly, midbass will be coming from behind, I can build two separate enclosures for the 15s, have them mounted on each side in the rear, angled for best performance..

I have plenty of room, but again, midbass would be coming from behind..

I love the sound of the W12s, but they have their limitations.. I love the sound of the 2226 (vocals and midbass are astounding) again, they have their limitations..

Again, looking to work with what I have, SQL, imaging a priority, linear response curve a priority, and the ability to produce massive output at the drop of a hat, clean, tight, balanced..

As you can see, there is much confusion on my part, my demands are high, funds are limited, but I've got nice equipment for starters.. Despite what the title says, there are obviously quite a few questions being asked here, so that title was a loaded question (kind of like downloading a program and getting all the bloat that comes with it because you forgot to uncheck all the malware packaged with it LOL)

Any info would be greatly appreciated!




Nominal Diameter: 380 mm (15 in)

Rated Impedance: 8 ohms (H)

Power Capacity1: 600 W AES continuous pink noise

Sensitivity2 : 97 dB SPL, 1 W, 1 m (3.3 ft)

Frequency Range3 : 30 Hz - 2.5 kHz

Power Compression4
at –10 dB power (60 W): 0.7 dB
at –3 dB power (300 W): 2.5 dB
at rated power (600 W): 4.0 dB

Distortion5
2nd harmonic: ≤ 1.0%
3rd harmonic: ≤ 1.0%

Highest Recommended Crossover: 1200 Hz

Recommended Enclosure Volume: 85-285 l (3-10 ft3)

Effective Piston Diameter: 335 mm (13.2 in)

Maximum Excursion Before Damage (p-p): 40 mm (1.6 in)

Minimum Impedance: 6.0 ohms ± 10% @ 25°C

Voice Coil Diameter: 100 mm (4 in)

Voice Coil Material: Edgewound aluminum ribbon

Voice Coil Winding Depth: 19.05 mm (0.75 in)

Magnetic Gap Depth: 8.1 mm (0.32 in)

Magnetic Assembly Weight: 6.8 kg (15 lb)

Bl Factor: 19.2 N/A

Effective Moving Mass: 0.098 kg

Positive voltage on BLACK terminal gives forward diaphragm motion.
 

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30 hz is possible, I really don't think 20 is remotely possible. and, in aa box large enough to hit 30 hz, your power handling is likely to drop a bit, not hugely..but noticeably.

I'd consider running these from 30 hz up to 120 hz or so, then having one of the nice jbl 5 inch component sets take over from there on up, good output from them and then you don't have so much midbass behind you.

personally I'd put that 2x15 cab in the car and see what cabin gain gets you around 30 hz, do this carefully obviously but you might be surprised at how low a 40 hz tuned box will go when reinforced from the van interior.
 

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Discussion Starter #3
bump
 

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Discussion Starter #4
30 hz is possible, I really don't think 20 is remotely possible. and, in aa box large enough to hit 30 hz, your power handling is likely to drop a bit, not hugely..but noticeably.

I'd consider running these from 30 hz up to 120 hz or so, then having one of the nice jbl 5 inch component sets take over from there on up, good output from them and then you don't have so much midbass behind you.

personally I'd put that 2x15 cab in the car and see what cabin gain gets you around 30 hz, do this carefully obviously but you might be surprised at how low a 40 hz tuned box will go when reinforced from the van interior.
Thanks so much for the info!

Here's a thought.. (With the PRS80 in mind) I've got a set of older PHD Pro Kit Modena 6.5" comp sets, essentially brand new (similar to their current AF)

Mount the 6.5" in the OEM door location (already setup with MDF adapters and Stinger dampener. Doors are rock solid, ready to transfer most of the energy produced by strong midbass drivers with minimal loss) tweeters in the sails aimed at my ears..

Now, would it be silly to assume I can use the JBL 15s from 40 to 80 or 120, along with a a pair of the JBL W12GTIs from 18hz to 40 or 50hz, by adding an active xo to the sub output of the 80PRS?

Already have a large cabinet built for the 2 W12s.. Since space is not a concern, neither is amplifier power (plenty of amps, high amp 14.6 volt alternator, 0 gauge wiring) I'm assuming the biggest hurdle at this point would be T/A getting skewed by splitting my sub output into a sub/midbass type deal.. Could the T/A be corrected by physical location of above mentioned drivers for this type of application?

See, I absolutely love the pavement splitting low end of the GTIs, I also absolutely love the pillowy thump, and kick of the 15s, they're warm yet detailed..

The PHDs are very transparent, I'm guessing they'd make a good match...

Am I complicating matters? Also, please bear in mind, this is a workvan which I also use to haul my bass guitar gear around with, so that 2 x 15 cabinet I mention is actually my bass guitar cabinet.. If I could keep it in the van as part of the system, then just unplug it and wheel it to and from gigs without ever having to unload it at home or storage, would be a win win situation for me..

I know it could all work, but could I get it to work well?
 

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Discussion Starter #5
I have these hooked up to an old school Punch 800A2 mono/bridged.. Cabinet is the huge 4648A, I believe tuned to 40Hz? Does well enough for music, Autotune from 80PRS did wonders, but still doesn't dig well into the sub 30Hz range..

I'm impressed with the sound, but I'm looking to install the W12GTIs I have, those will each be powered by its own JL 500/1..

I had the W12s briefly installed, I connected them to the 800A2 in stereo (3 ohms per side) large ported box.. WOW.. @ 3 ohms per side, talk about serious output from a mere 300 (ish) watts per side? Box was a hand me down, large slot ported box, approx 6 cf, setup for SPL.. I never got around to figuring out what the tuning was, I'm assuming it was tuned pretty high (considering the dips in output when listening to music after autotune.. Box was also falling apart, I temporarily fixed it up just to hear what it would sound like.. Def potential, but all wrong considering I did not know what the port tuning was.. It's been tossed to the curb, so I have no way of figuring it out now..
 

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If you've got a van, SUV or room to spare, PA style drivers are a definite go to! Amazing detail and clarity, pretty smooth from 38hz all the way up to 500hz.. (not that anyone would run that.. Still, autotuning with the 80PRS kept pushing my subs all the way up to 120hz, and the Hertz Milles all the way up to 120 Hz and above..

I have to reinforce the doors, I am definitely losing lower midbass energy to dampener which hasn't been reinforced by wood or a brace to prevent flex.. at the moment, there is essentially a 2' x 2' hole which was simply covered by hushmat.. I left it up to my cousin to install a piece of 1/2" ply on each door to cover the hole then hushmat, he skipped the critical plywood step, just pulled hushmat over the hole.. There is flex there, losing critical midbass energy, which is why I think the 80PRS keeps pushing the midbass to 120 hz and subs to compensate.. Technology, what an amazing thing..
I will reinforce doors then update..

Anyway, anyone ever consider running PA style speakers for subs, I can tell you from experience, if you've got the room, DO IT!!

Now I wonder what a single JBL 2241G 18" sub would do? Specs show a solid response from 30hz all the way up to 500hz, and it's a single 4 ohm voice coil..

Works well in a 4 cf enclosure (JBL sells a passive sub with that driver installed, I believe it's measurements are 24" x 24" x 18") amazing low end response, large, pillowy, deep.. Bass reflex design good for small room in live venue applications, designed to hit people in the front row, so they're 'near field?" Not sure if there's enough room in an automobile to make effective use of this, I supposed T/A would help? The 98Db sensitivity is what makes it so appealing to me.. that and the JBL clarity..
 
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