I'm starting my 2nd sub soon.

[Bent]

I've been expounding on the virtues of the Soundsplinter RL-p series since installing one in my AS-15 type box. I do like it a lot, however the venom of the DIY bug that bit me courses thru my veins once again, I've also ordered a 2nd 15" dual 4 ohm RL-p, and will parallel wire it in a new enclosure to get a combined load of 4 ohms again.

I'm considering a sealed alignment this time, outer enclosure dimensions will be 39 X 22 X 22, will this be adequate internal volume for two front facing drivers?, assuming all outer walls are doubled up 3/4 mdf and internal window bracing every 6"? or sould I utilize the full 48" width of a sheet for my long dimension?

T/S's are here:
Qts: 0.447
Qes: 0.508
Qms: 3.728
Fs: 27.487 Hz
Re: 6.1
Ls: 5.303 mH
Lp: 6.268 mH
Rp: 12.39
Dia: 330 m
Vas: 148.8 L
Mms: 231.4 g
Cms: 144.8 u
Bl: 21.90 T*m
n0: 585.0 m
SPL: 89.67 dB
Sd: 0.0806 m^2
Xmag: 27.4 mm
Xmax: 24.6 mm

And, would I be better off to build this a a down firing box with a large baseplate to elliminate walk, or would a dual vertical 15" driver assy be heavy enough to be stable?

I'll be buying a BFD from another member here for EQ and low end boost, and utulizing my non LT'd ADA 1200 plate amp in an outboard enclosure to power it with.

Or would it be worthwhile to use them in a ported box ala SVS since 6" flares are once again plentiful? I'd still tune it low, say 17Hz if possible, dual 6" (5.75") ports on one end...

Suggestions?

[ThomasW]

If you decide to go with a 48" depth, place the window bracing asymmetrically from front to back.

Don't forget to order the forklift.... :B

[Bent]

Well I'll be moving to a new home soon, the move will be paid for by my employer and a moving company will have to move the behemoth themselves. (I'm truly evil)

Would assymetrical bracing be preferred to avoid standiing waves within the cabinet, or is it for some other reason?

[ThomasW]

To avoid setting up any pattern for resonances.

Why not 2 boxes?

If you port them I'd go lower (12-15Hz) then build a rumble filter now that movies are putting in so much subsonic content

[Bent]

I certanly don't have a logical answer for why I don't build two boxes...
maybe vanity, pig headed stubborness, I'm just not sure.

I have to chime in again about the standing waves, I meant mechanical standing waves, not accoustic... (which, I guess, would be panel resonances anaways.)

HOw did SVS arive at their port lengths for their PB series with adjustable tuning by removing/placing port plugs? I'd think if the enclosure had a plugged port to reduce tuning frequency, that the single port would very likely have too much air velocity when just one port was being used.

[ThomasW]

I haven't sat down and reverse engineered their designs. Doesn't seem all that big a deal given the plots. I think room gain would obsecure much of the benefits



If you want to play I'd create a setup where you run a single port, then plug that port when watching something like WOTW with it's 3Hz content.

Use the BFD with one set of filters for the ported response and another for the sealed.

[Bent]

I'm not so sure a single port would flow air sufficiantly with dual 15 inch RL-p's sharing the same chamber. Or are you saying figuratively plug the port (which could well be plug the pair) for the extra low infra sonics?

[JonMarsh]

I certanly don't have a logical answer for why I don't build two boxes...
maybe vanity, pig headed stubborness, I'm just not sure.

I have to chime in again about the standing waves, I meant mechanical standing waves, not accoustic... (which, I guess, would be panel resonances anaways.)

HOw did SVS arive at their port lengths for their PB series with adjustable tuning by removing/placing port plugs? I'd think if the enclosure had a plugged port to reduce tuning frequency, that the single port would very likely have too much air velocity when just one port was being used.

That's exactly what tends to happen, but it makes the construction easier.

[ThomasW]

Or are you saying figuratively plug the port (which could well be plug the pair) for the extra low infra sonics?

Yep.... :T

[Bent]

Fed-Ex says the driver's been delivered, I just need to go pick it up.