what unit for a ELF sub?

[Phobos]

Hi, I'm thinking about building a sub in the smallest possible enclosure and i stumbled on this: ELF Subwoofer.
Basically, a sub unit (or more) ar put in a very small enclossure so that the resonant frequency is driven up over the crossover point.
Then the sub is equalized using a Linkwitz transform circuit.
This kind of projec requires LOTS of power (~250 W per driver at medium efficiency) and a unit that is capable of low distortions and good excursions.
I was thinking that a PA oriented sub would be ideal for this kind of project because they tend to be:
a) able to withstand abuse and come back asking for more.
b) very efficient, wich helps reducing power requirements.
I was thinking about 12" (maybe 2 units) or 15" (only one, cause it would be too big).
So, what units would you use for this project?

[richie00boy]

A linkwitz Transform is not used for this application, the double-integrator is, it's all in the article. It is possible to use a Linkwitz Transform, but you would not do it quite this way.

A PA driver would not be ideal for this as they have low Xmax and high Fs. There are dedicated sub-woofer drivers on the market that would be better choices.

[Phobos]

Yeah, I saw a lot of PA woofers that have low xmax and high fs but i thought that SUBwoofers for PA use would have higher xmax and lower fs.
Anyway my question was what would YOU use, meaning that i'm open to any kind of suggestion.

[richie00boy]

I used one of these http://www.shadowworks.co.uk/SW/HTML...ts/genesis.htm

[Phobos]

Thx man the specs for those subs are incredible at that price range! What kind of enclosure did you build for your genesis?

[richie00boy]

Approx 40 litres sealed, with a Linkwitz Transform. They are truly excellent drive units, and priced competitively.