Should I Try A DIY 12 or 15" Sealed Design??

[Fore]

Hello all,

Very informative forum firstoff. I recently seriously upgraded my 2 ch. system finally upgrading from these bass generous Von Schwiekert VR4 II's to a German made Tidal Audio 'Piano's
http://www.tidal-audio.de/english/st...shprodukte.htm
Some nice new silver wire, and an upgrade in amps to Canary 339 (50wt/ch 300B).
This is also my HT setup that I run thru a seperate system, same speakers. My room is in a bungalow house, 13'x11x8', but its open floorplan, and is connected to another room of the same size, and one open doorway on the backwall. Long story short, small room, but open so bass needs to accomodate this. I've had a Sunfire sub for a long time, and have been disappointed a long time too I want a new sub/subs that'll integrate seamlessly and give me organ producing bass (and by then, I'll be happy with the bass for HT). But room is very tight.

Anyway, I've been saving, and would love to buy 2 JLAudio F113 stereo subs. But I don't think I could fit them in one, and, I haven't saved that much money yet. So I've been wondering to try a diy sub. I'm handy with wood and have the tools too. But I downloaded WinISD and played with 3 drivers: TC Sounds TC3000 15", tc2000 15" and a Creative Sounds CSS SDX15 in a sealed box. I haven't tried the 12"s yet....but to be honest, a lot of it's above me and I"m having a hard time understanding it all. I've tried boxnotes too but only coming up with box sizes and int. vol. estimates. But I know see why buying a buying a 'plug and play' sub like the Fathom. I'm no acoustic expert and I'm beginning to think I shouldn't do it.

I picked these based upon alot of positive net reviews. My budget is say $3-500 per driver. (I've read it's more important to fit the right sub/subs in over a particular driver though. Also, thinking of something like a Behringer EP2500 per driver and some Behringer BFD or 24/96, and a mike. It'd be nice to have two inputs: One rca input from my Lexicon, and one speaker level for 2ch music?

Lastly, just to discuss box size. I can only have 13" deep if I wanted stereo subs that'd fit next to my mains. This really limits this option, my desired option to be honest. I could squeeze maybe a 18" cube behind the mains. Or I could just do one sub that'll fit between the couch and wall...like 18"W and whatever D and H.

Sorry for the length, but I realize the better you understood my desires and limitations, the better advice I'll get. Thanks for any suggestions.

Fore

[Fore]

Did I ask too much? Seriously, I hope not. Any suggestions guys?

[noodle_snacks]

You have one question mark in your post, and it doesn't constitute a question. It sounds like you want help picking a design and drivers. You need to set some specific goals, budget, low frequency extension, displacement, distortion, aesthetics etc. Then from those goals determine your best options.

Open floor plans are good in terms of room modes generally, however it does also raise the requirements for displacement. In my view a single 12"/15" driver would probably not be enough for your application (depends on spl requirements). Depending on your aesthetic goals, lots of large 15in subwoofers mightn't be good. You also have to remember that going sealed essentially shoots yourself in the foot in terms of spl at low frequencies.

Have you considered an IB?

[planet10]

Witgh your driver budget, 2 x CSS SD12 per side would be my choice (i have both SD12 & SDX15 sitting here now). I just did up a sealed push-push design for the SD12 and we will likely be going ahead and building them for a customer.

The shape almost satisfies your 13" criteria (they are 14" wide -- but i'd use them turned 90 degrees so that becomes 14" deep).

Mail me if you'd like to see the plans.

dave

[Fore]

Originally posted by noodle_snacks
You have one question mark in your post, and it doesn't constitute a question. It sounds like you want help picking a design and drivers. You need to set some specific goals, budget, low frequency extension, displacement, distortion, aesthetics etc. Then from those goals determine your best options.

Open floor plans are good in terms of room modes generally, however it does also raise the requirements for displacement. In my view a single 12"/15" driver would probably not be enough for your application (depends on spl requirements). Depending on your aesthetic goals, lots of large 15in subwoofers mightn't be good. You also have to remember that going sealed essentially shoots yourself in the foot in terms of spl at low frequencies.

Have you considered an IB?

HI Noodle_snacks. I guess I should've been more specific in my questions as you noted. Sorry. And yes, I'd love to have some ideas thrown out. To answer your questions: My goal is a sub that disappears accoustically, and gives me...I was hoping >20hz?...like 18hz? Something that'll be nice and clean say with mens deep vocals, and slammin' enough to make kickdrums sound real/realish. I don't want higher distortion for higher spls.
That;s what worried me about TC Sounds drivers, higher distortion comp. to others. Aesthetics are important too, but that's mainly a box making problem. And I'm afraid you maybe right too about single driver sealed box not being enough due to my open floorplan. I don't have room for a IB design. And keeping it sealed, at the expense of spls, allows more flexiible placement and in my experience, is tighter than a ported design.

Originally posted by planet10
Witgh your driver budget, 2 x CSS SD12 per side would be my choice (i have both SD12 & SDX15 sitting here now). I just did up a sealed push-push design for the SD12 and we will likely be going ahead and building them for a customer.

The shape almost satisfies your 13" criteria (they are 14" wide -- but i'd use them turned 90 degrees so that becomes 14" deep).

Mail me if you'd like to see the plans.

dave

Hi Dave, great to have you here! I've seen several of your designs and boxes. Very nice work.

So why do you suggest going with 12"s over 15"s? What's more 'ideal' cause it sounds like you're recommending the 12" do to room constraint for stereo subs...not that I may disagree, just what your thoughts were in suggesting a 12" design?
And the CSS SD12's over TC Sounds, or Precision sounds? So many drivers out there that again, I"m wondering why to this brand?

But a 14" box would work pretty well. How'd your built version turn out? Are you happy with the sound? Using a Behringer I assume? Amp? Any graph to see the output freq. response?

Thanks Dave.

[chops]

Originally posted by noodle_snacks
You also have to remember that going sealed essentially shoots yourself in the foot in terms of spl at low frequencies.

That's an absurd statement.

I don't know what sealed subs you've been listening to lately, but my 6.3cf SEALED push-pull 15's provide more than enough SPL straight down to about 14Hz, and enough oomph to pressurize the entire room down to 10Hz. And that's not even pushing it to its limits, either.

Just as a side note, I once measured a max SPL (via my SPL meter and TrueRTA) of 100dB @ 16Hz at my listening position, and it was loud as heck and still not pushing it to the limit.

[planet10]

Originally posted by Fore So why do you suggest going with 12"s over 15"s? What's more 'ideal' cause it sounds like you're recommending the 12" do to room constraint for stereo subs...not that I may disagree, just what your thoughts were in suggesting a 12" design?
And the CSS SD12's over TC Sounds, or Precision sounds? So many drivers out there that again, I"m wondering why to this brand?

I won't build a serious sub unless it is push-push (and stereo is a good idea). So 2 12s instead of 1 15, 2 15s instead of 1 18, Also you would be challenged to hit your size target with push-push 15s. All other things being equal a 12 will also reach higher than a 15. Something that is good when you consider getting a smooth hand off to the mains (of course, how high you take the sub is a factor)

CSS because i have them here to play with. ie familiarity.Keep in mind that CSS drivers are the spiritual descendant of the Adire drivers.

dave

[noodle_snacks]

Originally posted by chops



That's an absurd statement.

I don't know what sealed subs you've been listening to lately, but my 6.3cf SEALED push-pull 15's provide more than enough SPL straight down to about 14Hz, and enough oomph to pressurize the entire room down to 10Hz. And that's not even pushing it to its limits, either.

Just as a side note, I once measured a max SPL (via my SPL meter and TrueRTA) of 100dB @ 16Hz at my listening position, and it was loud as heck and still not pushing it to the limit.

It seems you are having trouble understanding my statement, it was perfectly factual. I was refering to the fact that you need a considerable low frequency boost to get flat response down that low. It also depends on what you consider loud, I don't personally consider 100db that impressive.

[chops]

Originally posted by noodle_snacks


It seems you are having trouble understanding my statement, it was perfectly factual. I was refering to the fact that you need a considerable low frequency boost to get flat response down that low. It also depends on what you consider loud, I don't personally consider 100db that impressive.

No, I didn't have any trouble at all understanding your statement. It is NOT true that you "need" considerable low freq boost to get a flat response. I know, I have the proof sitting in the next room.

100dB @ 16Hz isn't too shabby, not to mention that I still have plenty of power, power handling and Xmax to go louder. Also, I use ZERO equalization on my sub and it's perfectly flat from 80Hz down to 16-18Hz, including room gain.

And personally, I don't really care what impresses you.

[Fore]

Thanks Dave. My mains specs say they go down to 30hz, so I was thinking of crossing over at about 50hz. Do you still think 12's are the way to go then?