Four 12" subs in a blazer?

[ol'blazer]

just looking for some suggestions on how i should mount them, has anyone ever seen someone put four 12s in a square body blazer?

[panhandler62]

I would think a box right behind the rear seat.

Something generally like this (I think the whole is intended to be covered in the end.)

[BR3W CITY]

I have an 02 extreme, but the deck dimensions are close enough for comparison. We ran 2 Kicker 15's in MASSIVE ported boxes, taking up 95% of the back but putting up pretty huge DB numbers. It ran of a factory-freak Zapco 1kwatt class D monoblock, but we were convinced it put out well above 1k. The setup was switched by a different owner for four RE audio 12's.

Truthfully, I would build 4 seperate boxes setup for the correct volume (and ported or slotted as desired). Then build a facia for them. This makes it much easier to service, access and design from a volumetric standpoint. I've done and seen this done well when combined with fiberglassing for show boxes.

[ol'blazer]

i have four kicker cvr subs, with two rockford 1000w class d mono blocks. im not sure if i want them all in seperat boxes. i would just built one with all the combined airspace.

[ol'blazer]

Originally Posted by panhandler62

I would think a box right behind the rear seat.

Something generally like this (I think the whole is intended to be covered in the end.)

i love that look. i wounder if thats plexie glass?

[panhandler62]

I think that is an installation part way through. I was mostly looking for a picture of them tucked up against the back seat like that. I think that, in practice, you would at least want baffles between them so they don't get "muddy."

[BR3W CITY]

I suppose if they were wired together in a mono setup, you could run it like that for pure "boom". That setup doesn't look like its getting any more internal work, I think its just waiting on a front (plexi/acrylic etc). Thats just me judging by the finished edge on the front of the box.

I have run unbaffled/unseperated subs like that before, but with 4 subs I wouldn't run them like that again. I'm a fan of stereo subs from the start, for metal etc that can take advantage of the seperate channels.

[ol'blazer]

I'm going to be running two subs off one amp and two off the other, I'm not piggy backing them all together, should I keep two and two seperated or all individual?

[BR3W CITY]

Originally Posted by ol'blazer

I'm going to be running two subs off one amp and two off the other, I'm not piggy backing them all together, should I keep two and two seperated or all individual?

Are you running one amp L and one amp R (i.e amps in stereo), or are you running a sub-out signal (mono) to each? Or I guess you could run two seperate pairs of stereo'd subs.

If you want to run 2 and 2, using one amp for each channel, then you can keep them divided as such. FWIW tho, if you go through the work of doing each sub individually, no matter which amp setup or output setup you run, you'll have the cleanest option. By that I mean; if you keep them separate, you can run them any way you want, without having to go back and think about how it will affect the system. Once the boxes are sized and ported/baffled, then you have the freedom to run mono, stereo, mono at separate freq's (like if you wanted two different sized subs). You also get the redundancy that it offers. If you have an anomaly that could damage the sub, you don't risk allowing collateral damage.

[motornut]

I'd say that box is mono,one open box, all hit together,
could be a flip up hole cover laying down or a material port cover?
I do seperate boxes,wired left/right.
But once built, you can wire them either way,
but you don't one affecting the push of another
muddling is a good word!
say one (L) is powering out it could pull the other (R) non powered in during a note/hit

[ol'blazer]

Originally Posted by BR3W CITY

Are you running one amp L and one amp R (i.e amps in stereo), or are you running a sub-out signal (mono) to each? Or I guess you could run two seperate pairs of stereo'd subs.

If you want to run 2 and 2, using one amp for each channel, then you can keep them divided as such. FWIW tho, if you go through the work of doing each sub individually, no matter which amp setup or output setup you run, you'll have the cleanest option. By that I mean; if you keep them separate, you can run them any way you want, without having to go back and think about how it will affect the system. Once the boxes are sized and ported/baffled, then you have the freedom to run mono, stereo, mono at separate freq's (like if you wanted two different sized subs). You also get the redundancy that it offers. If you have an anomaly that could damage the sub, you don't risk allowing collateral damage.

im running two serperate amps. not L and R, i will probably cross over from one to the other on a sub out

[BR3W CITY]

I think you miss my question; Even with seperate amps, you can have one just playing the L channel, and the other the R channel. Meaning that when they all play, its stereo 2 and 2. Otherwise your running each one mono OR running an L and R to EACH. I wouldn't bothering running 2 full pairs, as the end result is still 2 and 2 on stereo.

[gramps77]

everything you could want to know once you start going beyond a single subwoofer.
http://stevemeadedesigns.com/home/

Mounting 4 subs like that will NOT cause any sound to get "muddy" if your speakers are working correctly and the box is designed correctly. Theres a guy putting 8 12s in his extra can Ranger and they all share the same airspace. Building a bunch of single boxes together will not make anything easier cause now you are having to cut more, screw/nail more, and seal more. Generally, you'll want all your subs running off the same signal/wiring and Ive seen up to 24 speakers wire off the same single bridged channel coming off an amp. Car audio these days has gotten OUTRAGEOUS with 10000 watt amps and multiple alternators to provide power. 5 or 6 320 amp alternators is a LOT of current.

and that pic of the 4 JL Audio subs is most certainly its finished design with plexi. You will rarely see a box that is finished internally and be all closed up.

[BR3W CITY]

Originally Posted by gramps77

Generally, you'll want all your subs running off the same signal/wiring and Ive seen up to 24 speakers wire off the same single bridged channel coming off an amp.

Not trying to throw up a BS flag, but mathematically that would mean that their either running really low impedance if parrallel, or really high impedance in series.

24x 8ohm speakers in parrallel would be like .33 ohms total
or
24x 8ohm speakers ~192ohm in series.

Now I've seen systems go .5 ohm and less, so the 1/3 ohm setup in parrellel isn't impossible, but I really can't imagine the setup in series.

Can you show us the setup in question?

[gramps77]

Running a combination of series/parallel. It was 24 Soundstream 12s running off a Soundstream 10.0. Your math is right if you stay series OR parallel but you can mix it up too. There were sets of 4 wired wired parallel then series

[ol'blazer]

haha this is beyond me!

[gramps77]

Originally Posted by BR3W CITY

Not trying to throw up a BS flag, but mathematically that would mean that their either running really low impedance if parrallel, or really high impedance in series.

24x 8ohm speakers in parrallel would be like .33 ohms total
or
24x 8ohm speakers ~192ohm in series.

Now I've seen systems go .5 ohm and less, so the 1/3 ohm setup in parrellel isn't impossible, but I really can't imagine the setup in series.

Can you show us the setup in question?

easiest way to do it, in my example, is to wire 6 sets of FOUR speakers parallel which gives you a total of 1 ohm per set. Then you can wire them either series/parallel for a final load at the amplifier of 1.5 ohms(newer amplifier that can handle it, or, those old Soundstreams) or in series with a final load of 6 ohms which in a mono configuration at the amplifier the amp would "see" 3 ohms, which is perfectly acceptable even with the older amps.