3015 lf box that plays down to 30hz??

[justint]

anyone make one of these recently or is there a prior post.. i have a 3015lf that I would like to make a box for that needs to play down to 30hz with at least 115db. Doesnt have to play higher than 80hz. Any help would be great. Thanks

[littlemike]

Got something close, but not quite. According to the model, it is -3 dB at 33 Hz, and 115 dB is no problem at all.

Interested?

[jbell]

A few more requirements on size, etc would help.

A simple 200liter ported tuned to 30-32hz will do the trick.

(I happened to use 240cm2 port by 20cm long in hornresp@28v)

I'm sure mike has something better than this....

[justint]

smaller on size would be better as it is for the living room.. but yes send any plans specs you have .. Thanks..

[littlemike]

Small? 30 Hz? 3015 LF? Not gonna get all three. The 3015 likes a BIG enclosure, no doubt about that. I'm looking at 30" deep, 36" tall, and 23.5" wide, external. if that is too big, I can see if it is possible to squish the width any further.

This is a tapped horn, and is 100 dB 1W, 1M 2pi, -3 dB @ 33 Hz. 100 W gets you 120 dB @ 7 mm excursion, 250 watts is essentially xmax, at around 125 dB, 600 watts gets you north of 125 dB, within xmech.

30 Hz highpass is not an option.

[justint]

taller but not so deep? depth more like 20" area but I could go taller.. the width at 24" or less is fine. And correct I will not have a high pass.

[jbell]

Originally Posted by justint

correct I will not have a high pass.

no high pass = no tapped horn

don't build it.

Any one here good at designing PR cabinets can give a suggestion for a cube with 3 of these?
http://www.parts-express.com/pe/show...number=295-496

[jwmbro]

small footprint but tall? How about a single fold tapped horn.

20" x 20", but 5 and a half foot tall:



121dB with -3dB point at 30Hz. Highpass mandatory.

EDIT: oops, posted this before I saw that you don't have a highpass. Could get about 115dB within xmech, but exceeding xmax below 21Hz if you didn't use the highpass with it.

[justint]

ok so any other suggestions besides the tapped horn? or I guess i could buy a amplifier with a high pass?

[jbell]

Originally Posted by justint

ok so any other suggestions besides the tapped horn? or I guess i could buy a amplifier with a high pass?

Passive radiators don't have the unloading issue below system resonance that ported or tapped horns have.

A Jurassic Park T-Rex stomp turned up in a TH without a high pass = one very cooked driver.

I'm kinda intrigued by a 3015lf / PR design, and may spend some cycles investigating it.
The rule of thumb is that you need 3x the Vd of your driver, in your PR's. 3 of the dayton 12's @10mm xmax each doesn't quiet get you there, but it's close. (and they are cheap)

A PR design would allow you a small enough box to be allowed in the living room as well.