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I have 5 of the 18's. I bought all of them off of Ebay or through people I knew. The 2 online stores that sell them are Mobile Sound Works and Woofers Etc. Both are quite expensive and a dealer if you can find one will be probably even more so. However one of those 2 online vendors has been selling the 12" model for $500 shipped on ebay. I think the 15" is about $620 or so. I've never seen them sell the 18". only small dealers or private individuals.

I'm curious...What size were you interested in and what do you have in mind?
 

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Discussion Starter #6
I'm only looking for an 18". I'm looking at doing a LLT with PR's for 60% music 40% movies. About 35 to 40hz x-over for music, and 60hz or so for movies at 24 or 48db per octive.
 

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If you really want to use that driver I can help you out. It is a beast but the 18 is NOT an easy driver to use and if you are going to pay that much for an Uber driver you want to make sure you get maximum performance from it. A pair of cheaper drivers like RLP's or Mal-X's will most likely outperform it, but they will require twice the enclosure volume to do it.

First things first, you should forget about using PR's with it. There are no PR's made that can cope with the displacement that will be required when that driver starts moving in a massive way, unless you want to use 4 18" pr's. That's right 4 .

And say that you did use 4 PR's, well this then ends up getting the box so large to tune the PR's low like you would want to with this driver, that you might as well go ported. This brings in a whole other problem, which is that you really need a 10" port, or even larger on this driver. It will easily overload and compress an 8" port at high volumes. Mine is using a 10" based high flow port design and I still get some serious compression if it is really pushed near the tuning (pretty rare really but hey you do want to get every bit of performance you paid for right?). I wouldn't tune it any higher than 15hz and ideally around 10-12hz. Even in a 25cu ft box a 10" port is around 60" or longer to tune that low. This is why I ended up using a power port design. Even tuned to 11hz in a box that large it is in no danger of over excursion until 9.5hz and over 2500w.

Also you will need a big power amp to put on it as it will easily handle an EP2500. If going with a resonant system I recommend the Crown CE4000 which is what I use. It is just about right to where the amp and driver both run out of gas at the same time. If you went sealed I'd recommend a QSC PLX3402 or 3602, because the Crown rolls off below 10hz and the QSC's are flat till 5hz. Sealed is a much easier implementation with this driver and it will not disappoint in about 8cu ft with a real 3KW behind it. This is the way I'll be going with my other 4 XXX's.

The good news is that if it's done right it can come close to matching the performance of a pair of other high performance 18's in the HT range (<30hz) in a ported system half the size. If you use it sealed it is pretty much the same story. While other drivers are running out of excursion and compressing or damaging themselves trying to produce the really low stuff it will just happily belt it out. This is bandwidth uniformity. It won't compress the deepest bass until much higher levels than most drivers.

Sorry about being so long winded. I spent MONTHS formulating the ported design I went with and how to get the best performance out of that driver while it sat there unused. :coocoo:
 

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Discussion Starter #9
And say that you did use 4 PR's, well this then ends up getting the box so large to tune the PR's low like you would want to with this driver, that you might as well go ported. What is the advantage of using a port over PR's besides cost? I thought PR's would be more sensitive to the lower frequencies?
 

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Discussion Starter #10
Sorry Ricci, I need to learn how to do a quote. If I tune the sub to 10hz, would that be the only frequency the PR or port would produce, or would they play the same frequencies the woofer plays?
 

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It's a mixture of the PR/ port output with the drivers output. right near the tuning frequency the PR's will be doing virtually all of the work. As the frequency increases the PR will output less and the driver will output more until the PR's have almost no contribution and the driver does all of the work higher in the bass range.

Besides cost the advantages of using a port is that there is nothing to wear out, it's lighter, and you won't break a port if you over drive it. The advantages of PR's is that they don't have the resonances associated with big ports, they take up less space in the enclosure, they make tuning low possible in enclosure sizes that other wise wouldn't be possible and they look cool.:bigsmile:

Do you use winisd? You can model a PR enclosure and it will show you the passive radiator excursion at various frequencies and power levels.
 

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Just Google winisd box design program. It's a free download. REW is available here, but it's for measuring your frequency response, decay and many other things in your room. You'll need about $200 in equipment to get that running but it is well worth it.
 

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Try the Pro. I think that's the one everyone uses. There's also another program that is a bit more complicated called unibox. You need excel or a simulator but it's free too.
 

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There isn't one anything from 06 on up is the same. The 05 and earlier models are a completely different driver though.
 

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Like Ricci mentioned, same from 06 and up... actually we were selling them about June of 05, but the 05 is commonly referred to as the last of the XBl motored XXX subs. The newer version uses a split coil design, not split gap like the older one.
 

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Discussion Starter #19 (Edited)
Ricci, I've been trying to use WinISD on the RE XXX for a couple of days with no success. What driver parameters did you use? If you could post or Email me your WinISD file that would be great. Thanks.
 

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Let it auto calculate them. If the Q values or others do not match exactly, its really not a big deal. Enter the RE, SD, BL, values first. These are easily measurable and concrete. The parameters that are missing are the MMS and CMS.
 
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