looky What I Just Got

[sourceoneaudio]

We have reached max X-MAX with the Parts Express passives. So weighted and tuned correct they do not pass mustard. We are very close to picking up pieces of cone material off of the ground. Crazy Excursion during DTS formatted movies. Music is good, and bass response is tight, and punchy in the upper volume levels. So far these subs are very impressive, subtle low frequency passages during movie play back are very defined and amazing, I would recommend the use of these drivers for any application.

So as far as new passives go I'm looking at these brands.

http://www.tcsounds.com/tcvmp.htm#specs

Seems they are one of the few manufacturing high X-MAX passives, 80mm peak to peak, and 500 to 2500 gram weight capacity.

Specifications



3" wide variable mass load adaptor
500 grams up to ~2500 grams of variable mass (90 gram iterations)
xmax of 40mm (one way linear compliance)
Single ultra wide 10" poly-cotton spider
Cast aluminum basket with high gloss metallic powder coating
Tall (NBR) surround for high excursion and better longevity than foam

Includes up to 2000 grams of selectable mass washers

High quality thermal flexible epoxies to ensure longevity
Rigid lightweight brushed aluminum cone
Hand built in our San Diego, CA factory


*mounting depth includes 2.0" extra spacing for excursion


Thiele Small Parameters



12" TC-VMP
Vap0.0 Dia250mm Vas0.0l V-Fs4Hz-24Hz cms0.0m/N V-mms500g-2500g
15" TC-VMP
Vap0.0 Dia325mm Vas0.0l V-Fs4Hz-24Hz cms0.0m/N V-mms500g-2500g
18" TC-VMP
Vap0.0 Dia390mm Vas0.0l V-Fs4Hz-24Hz cms0.0m/N V-mms500g-2500g


This is the other brand I'm looking at, and I have seen threads on th LH forum in regards to their use. Stryke Audio SA-PR18-1600. But I think production has stopped for I can't find a seller of them new. The link below is no longer carrying them.

http://www.acoustic-visions.com/~acoustic/products/passive_radiators/stryke_pr18/indexold.shtml

So needless to say the volume control has been regulated depending on the source input.

The LH member who is helping me tune these bad boys has run the Stryke Audio 18" in a simulation and it seems to do the trick. Stated below are the results. This is the passive I would like to use if I can find some????
The above PR will work just fine, but the cost is much higher, and they are out of stock on them.

I modeled the 1600g in 5 cu ft, it looks absolutely bullet proof - Group delay is very low, power handling is off the chart, cone excursion for both is safe at 105db+ from 20Hz on up....dayum....

Worthy of discussion in public. I'm only parroting what I see in ISD - I'd like to hear others' views...

SA-PR18-1600

FS 4hz

Mms 1600 grams

Qms85

SD 1200cm^2

Vd 9L

Vas 1840L

Xmax 76mm p-p

If anyone can help with this issue in finding, or wanting to sell a couple of the Stryke Audio passives let me know.

J/S-S1A

[clmrt]

Here's what I've run so far -



Can't attach a .wpr

I can email it to anyone who'd like to see it.

5 foot box, 200 watt input, three scenarios -

1x PE 15" PR
2x PE 15" PR
1x 18" PR

[sourceoneaudio]

We have reached max X-MAX with the Parts Express passives.


J/S-S1A

Well I have spent more time messing around with these subs because I have felt something was missing. Yes Clmrt and I have discussed putting them in a bigger enclosure, but I still felt that I could get more form the cabinets in hand.
So I messed around with adding more weight, pulling insulation, ended up putting back the insulation to a thinner layer on the bottom and putting the weight back to first calculation. While I was doing all of this I noticed the spider had come unglued from the basket. This is bad because it threw the alignment off under extreme conditions, and I was getting a serious blapping. The extreme x-max issues as I stated above partially was due to this new discovery. This was not the fault of adding the JBL's in, I have had this problem for a while, never expected or even looked for it since they are not that old. So I re-glued back to the basket, and it's all better now. I also reduced the sub out to -2db and now that they are broken in, which does take a while, the low frequency reproduction gets more and more impressive every time I listen to them. Let me tell you what, this is the first sub design that I have ever done that during a movie formatted in either DTS, or Dolby Digital when a low passage comes out from no where, and I did not expect it, I about jump off the couch. Definitely a HOLY SHIT experience! So needles to say these W15GTI's kick some serious ASH!
So bigger box? Still up in the air. $$$

J/S-S1A

[DS-21]

Even with the PR fixed, going to dual opposing PR's is a very good idea. Though the linear throw of the W1-GTi series does not quite measure as [url-http://www.diymobileaudio.com/forum/showthread.php?t=11864]one would expect it to[/url] (notes about a W15GTi measured further down in the thread) with a 15", 22mm xmax PR you're still on the edge even if the realistic xmax is only ~12mm on the woofer itself. A second one will also have the advantage of cancellng out box vibrations.

[sourceoneaudio]

Thank you for the information. I copied the link so that it functions.

http://www.diymobileaudio.com/forum/...ad.php?t=11864

http://www.jblpro.com/pub/technote/J...-33%20rev3.pdf

Jeff
J/S-S1A

[Thom]

I've played with this woofer a tiny and I mean tiny bit. They must have used steel where the pro woofers use aluminum because they're supposed to be light and this bugger is heavy as hell. I've really only tried it in a sealed box that was designed for a pickup and it wasn't what I expected at all. Going to try ported but I expected, stick a DC300 on it with an active crossover and be impressed and it's going to need more than that.

[northwood]

cool