Which 15s would you use on 5k rms in a 4th order?

[ciaonzo 5,000+ posts]

A ported enclosure is a 4th order and that picture above is not a bandpass.. so, i dont know.

I understand what you mean, and you are correct. But I think when folks 'round here say 4th order, they are actually describing a 4th order bandpass. Looks like a panel is removed on that photo. Replace it, and you have a bandpass enclosure. I'm uncertain if that's what's going on in the photo. Just sayin'.

 

[hispls 5,000+ posts]

Good point.

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I'm thinking 2 drivers instead of just the one. I'd have room for for that and have no interest more than that simply because of power. If I use a 5k then I can run 2 subs that aren't quite as powerful as the Evils but will still wang. I'd like an air mover. Should I focus on the higher xmax drivers for that reason or is it really more install dependent? Also, most of these high powered 3 and 4 inch coils seem to have relatively low qts. How important is that measurement to 4th order application?

I don't really care for bandpass. IMO by the time you get them to actually play a wide bandwidth you might as well be running sealed. If your idea of a good bandwidth is a 15hz spread than bandpass may help and even low q drivers should work (though if you insist on that alignment you really should do your homework modeling subs before you buy and plan around that).

From my experience buying subs with exotic softparts adds significant cost to recones and the extra 5mm of x-mech is likely inaudible by the time you're at x-mech in standard 12 sopke frame territory. If you're going for whale songs try to find some LMS-4000's or XBL^2 but again recones will be expensive.

Using your box and subsonic filter appropriately you should not be reaching mechanical limits on a pair of 12's on 12 spoke frame, even less likely with 15's. 8" spider, 3" coil is cheap to replace and easy to find parts (moreso with 4 layer coils).

 

[germanyt 10+ year member]

I don't really care for bandpass. IMO by the time you get them to actually play a wide bandwidth you might as well be running sealed. If your idea of a good bandwidth is a 15hz spread than bandpass may help and even low q drivers should work (though if you insist on that alignment you really should do your homework modeling subs before you buy and plan around that).
From my experience buying subs with exotic softparts adds significant cost to recones and the extra 5mm of x-mech is likely inaudible by the time you're at x-mech in standard 12 sopke frame territory. If you're going for whale songs try to find some LMS-4000's or XBL^2 but again recones will be expensive.

Using your box and subsonic filter appropriately you should not be reaching mechanical limits on a pair of 12's on 12 spoke frame, even less likely with 15's. 8" spider, 3" coil is cheap to replace and easy to find parts (moreso with 4 layer coils).

I reckon my ideal is 25-50hz. I listen to mostly rock/alternative (mostly 90s) but with any loud setup people wanna demo and you gotta throw in the bass heavy decaf and remixes. To be honest I'm just on kind of a kick with 4th orders. I just recently build one and felt there were areas I could improve upon my buiding in general. Ported is easy enough but I wanted to maximize output. However, I would rather have a flatter response and lose a db or two. If I wall off my car on 5k I'll be upset if I cant find a 50 somewhere. Beyond that the flatter the better. As for modeling, i have winisd and have no clue how to use it. Or if that is the proper program to begin with.

 

[hispls 5,000+ posts]

I reckon my ideal is 25-50hz. I listen to mostly rock/alternative (mostly 90s) but with any loud setup people wanna demo and you gotta throw in the bass heavy decaf and remixes. To be honest I'm just on kind of a kick with 4th orders. I just recently build one and felt there were areas I could improve upon my buiding in general. Ported is easy enough but I wanted to maximize output. However, I would rather have a flatter response and lose a db or two. If I wall off my car on 5k I'll be upset if I cant find a 50 somewhere. Beyond that the flatter the better. As for modeling, i have winisd and have no clue how to use it. Or if that is the proper program to begin with.

A guy I know was getting 150 and small change out of his civic walled off at the trunk with various single 15's and 5K. He put a fair bit of work into the box and it was more DD style box/tuning and that style sub did well. He broke a lot of woofers! In fact after seeing his LV 6 fall apart 3 different times pretty much turned me off of DC. The motors were solid but their softparts and/or build quality was pathetic.

All the "gain" you get with bandpass comes at the expense of bandwidth and your high frequency is attenuated by the port which will neuter your 90's rock and punk type music. which needs to stay lively up into the 60's unless you have room for some big and enclosed midbass woofers up front.

I did one bandpass that I liked a long time ago, 6 JBL 12's in the trunk of an old Lincoln Towncar. If you recall the space of those trunks (minus the spare), the point was simply to get the bass into the cabin via the rear deck, I expected sealed box performance and that's about what it did. The guys doing big SPL numbers with bandpass are tuning it to be a one-note-wonder or are using so much power and cone area that sealed would be just as loud.

I've found winISD pretty accurate, rumor has it that you can pirate a copy of Bass Box Pro via torrent if you're that sort of person. Bass Box Pro is slightly more powerful but IMO can tend to be finicky and overly complex.

Anyway, it's your ride, do what you like. I'd highly recommend doing sealing and making a way to remove or modify the box if you're not happy with response. Google "trunk wall spl" and poke around images there's some pretty good ideas there that you might be able to follow into some build logs.

 

[mlstrass 5,000+ posts]

sundown X or zv4, FI sp4, crossfire xsv2 all work well in 4th orders. I personally run zv3's in a 4th and they play 30-60hz pretty loudly....

 

[Papermaker85 5,000+ posts]

only bandpass boxes i like are 6th order and boy are they hard to build. i see alot of peeps loving single reflex bandpass but i personally have had better results ported. the BP just isn't as efficient both are 4th order but some drivers dont do well at all in a BP. drivers that do good sealed tend to do nicely in BP.

that being said Id probably go with the sundown team or the ascendant audio team..

 

[Boomin_tahoe 5,000+ posts]

Sundown x or zv4

 

[Papermaker85 5,000+ posts]

how much room do you have? why no do 1 15 in a folded horn?