15" DIY Woofer/sub cab for bass guitar

[ERiley]

Hey all--

Not exactly a noob, but close enough to get spanked pretty good in this company...I'm one of those guys who has a driver in-hand and wants to build a box around it. Try to be kind...

The speaker is an Eminence Delta 15LFA. I've searched more than a few DIY sites like fEarful and Bill F's neat design pages, but none of the plans included the 15LFA as a candidate driver. I know I could take the T-S numbers to winIsd, but I'm far too brain lazy to work dimension configurations, bracing logistics, etc...

Is anyone here familiar with the speaker in question to suggest an established cabinet design? I'm open to front-loaded, horn loaded, folded horn, whathaveyou. The system will be bi-amped with an Ashly crossover and QSC power. The top cab is an Eden D210XLT.

The Delta 15LFA has an EBP of 75, but a sealed enclosure won't accomplish my needs, so that's about the only scenario that's out...

...Oh, and I would really like to keep it under 75 total lbs if I can. Besides being brain lazy I'm also past the age of throwing an SVT 8X10 around by myself...

[jefffluker]

Re: 15" DIY Woofer/sub cab for bass guitar

Ran the numbers thru WinIsd. Ported enclosure curve is flat to 40 Hz. Optimum box volume is @ 15 cu. ft. Reducing BV degrades first octave response. Sealed, it's still rather large--7.5 cu. ft. This one is tricky.

[ERiley]

Re: 15" DIY Woofer/sub cab for bass guitar

Wow, big box. Thanks for punching those numbers in, Jeff. Maybe this 15 belongs in a 16-ft exponential horn...

[billfitzmaurice]

Re: 15" DIY Woofer/sub cab for bass guitar

The speaker is an Eminence Delta 15LFA. I've searched more than a few DIY sites like fEarful and Bill F's neat design pages, but none of the plans included the 15LFA as a candidate driver. .

That's because it's obsolete. The small xmax makes it marginal for use as a sub. The high Qes makes it not useful for horn loading. It will go low ported, but only in a huge box. Sealed it needs 7 cu ft for a .8 Q, and even then only has a 55Hz f3. In short, it really has no redeeming qualities. I'm surprised than Eminence hasn't retired it.

[ERiley]

Re: 15" DIY Woofer/sub cab for bass guitar

Hmmm...Not promising then. I also have a pair of Eminence OEM 15s from Ampeg cabs that Eminence told me were very close to Delta 15's. Perhaps those are what I'd be better off working with. One is 16 Ohm and one 8, so pairing would be...Awkward...The 16 Ohm model came out of an isobaric enclosure, the 8 Ohm was purchased from a repair shop many years ago. The LFA was chosen for it's relative youth and the reported power rating...

Back in the closet with it, then...

[wg_ski]

Re: 15" DIY Woofer/sub cab for bass guitar

It's just not a 'high performance' driver. What do you want for $100? Certainly can't get the world, but it would be fine for electric bass in the Eminence suggested 'large vented box' (5.5 cubes) with a reasonable amount of power, say 200 watts. Just won't go stupid loud or make the earth rumble. That's what the PA is for.

[billfitzmaurice]

Re: 15" DIY Woofer/sub cab for bass guitar

Hmmm...Not promising then. I also have a pair of Eminence OEM 15s from Ampeg cabs that Eminence told me were very close to Delta 15's.

Delta 15s are used a lot to replace the OEM driver in low power tube driven Ampeg combos, as they have the same tonal characteristics, and 50 watts or less isn't a problem with their short 2.7mm xmax. They're of pretty limited value with a high power amp, or trying to push lows with any serious volume.

[ERiley]

Re: 15" DIY Woofer/sub cab for bass guitar

Glad I chose to sign on and ask those who know. I still want/need a sub, but I'm obviously going to acquire the right driver. Thanks for the education gentlemen...The cabs I can build, the component choice? Like I said...Thanks.

[wg_ski]

Re: 15" DIY Woofer/sub cab for bass guitar

So how many watts are you running on the low end? The "right" driver will depend on this. As a point of reference, 500 watts will require 7mm of displacement capability - assuming you want the low E use a 'normal' 15" driver (96dB/1w/1m).

[ERiley]

Re: 15" DIY Woofer/sub cab for bass guitar

Im reading up on the Kappalite 3015. I believe it's in the 7+mm range...

I play fretless four string pretty much exclusively, but the singer we work with has us tuned a half step flat (via a DigiTech Drop), and yep, I do a fair mess of drop-D.

[ERiley]

Re: 15" DIY Woofer/sub cab for bass guitar

Delta 15s are used a lot to replace the OEM driver in low power tube driven Ampeg combos, as they have the same tonal characteristics, and 50 watts or less isn't a problem with their short 2.7mm xmax. They're of pretty limited value with a high power amp, or trying to push lows with any serious volume.

Then that's where the Delta 15s will reside; in low power practice/small venue stacks. I have no issue with upgrading drivers. It's one of the reasons I signed up here...

[billfitzmaurice]

Re: 15" DIY Woofer/sub cab for bass guitar

Im reading up on the Kappalite 3015. I believe it's in the 7+mm range...

I play fretless four string pretty much exclusively, but the singer we work with has us tuned a half step flat (via a DigiTech Drop), and yep, I do a fair mess of drop-D.

For sub use you'd want the 3015LF.