I am guessing I am not a single 15" sub kinda guy

[1sashenka]

Well folks, for the longest time I had a hard-on to try a single 15" sub set-up as I never had one before. I have experienced a single 12", a dual 10", a dual 12", a triple 10" - all sealed, and a single 18" ported.

And it seemed my time has come to try one when the Xcon came out, and I have been anxious to get one of those in 15" size and seal it in around 2.25 cubes. The other day, I tried in my car a single 15" JBL GTI in a ported apprx 3 cubes box on around 850 watts. That sub is supposed to be one of the best, but it did not meet my expectations. I measured good db's, but it sounded strained with tons of distortion at loud volume. I could push my dual sealed set-ups of tens and twelves to same loudness, but they do it with much more ease without break-up and bottoming out on same power. I am guessing with my high expectations for occasional blairing and still remaining good control a 15" sub cannot give me. It seems being a single sub it strains too much, but two subs remain cleaner at high volumes as they are sharing the load. Dis anyone else have these findings? If this is the case, I may just scrap the single 15" Xcon project, as it may not give me the clean sound at high volumes as two 12's can on same power of lets say 1500 wrms. I realize that Xcon will have potential to be pushed further than the JBL, but I am guessing it will still show signs of strain being a single sub. It would appear, that a single 18" ported sub would be on par with two 12's in clear controlled output at high volumes, and I just dont have the room for an 18" sub, so I guess I am stuck with two 12's as my fave sound to sq/spl ratio, as two 15's would also take too much space. Any thoughts?

BTW, I noted that JBL GTI and CSS SDX series subs have a very similar sounding sonic signature and output. A very similar performance, only CSS is much cheaper.

[hobie1dog]

you should have listened to a SI Mag 15

[ku40]

You shouldn't generalize like that. Just because that one 15" didn't meet the bill doesn't mean that all of them won't. A single 1000 watt 15" sub will handle 1000 watts the same as two 500 watt 12s. But because the 12s have more surface area, they should be able to get a little louder.

But if you want two 12s, go for it.

[Electrodynamic]

I agree - generalizing about a single drivers performance compared to a dual drivers of a different manufacturer isn't being fair to either party.

Also keep in mind that distortion is ENGINEERED into some speakers because that is what the manufacturers customers are used to hearing and that's what they like to hear.

However, I just looked at the Klippel data on the GTI and I'm concerned about you listening to the GTI in a ported enclosure because I would NOT port that driver. It's suspension is stiff enough for porting, but the ratio of Qts to Vas isn't what I would like to see for a ported application. Ie, the Qts is too high for a ported application. The inductance is low enough (0.9 is GREAT for a driver that size!), but I would not port that driver. Is there a way you can listen to that driver in a sealed enclosure?

BTW: Why are you looking at an XCON? It's a driver that is based off of the BTL (it's not the exact same driver, but you do see the physical similarities don't you?). A different coil and spider pack can change a driver considerably, but it's still going to be heavily over-motored for any setup with the letters S and Q next to each other. Not to mention that it's going to weigh a ton. You can get better SQL performance from a LOT of other 15's besides the XCON. If you thought the GTI sounded distorted, wait until you hear the XCON.

[1sashenka]

Thank you for your opinions. That is what I wanted to hear. About the GTI sub, there was a lot of hype around, so my expectations were really high. Now, I recall having a single ported 12" Mag v2 for about one year and I pushed it hard without major problems, but it was so long ago, I already forgot about that driver.

Nick, you're probably right about porting that GTI. I havent ported my subs since that last Mag, and my experiment may have been flawed because that GTI was not sealed. That is why I started the thread to hear other angles as I was deeply disappointed with the performance, and thought something may have been a miss.

The reason why I had a hard-on about the Xcon is simply the hype around it, as people kept buzzing that it is supposed to sound as clean as an Icon or Fi Q with flat response and it got louder. Seems like a win-win, but I value your opinion, and if you say it is based of the BTL, and people were saying it is just a dirty sounding SPL driver. Thank you for clearing all this up, and now I am no longer interested in the Xcon. It was sort of going to be my last project with loud drivers, as I am now getting into more SQ oriented subs, but I surely need two of them as I still like it loud sometimes. I am really getting into the sub sound Hertz Mille, Morel Ultimo, Aurasound offer. They all sound similar to me, and I am loving that type of bass. Right now, I am running the DLS Nobelium subs and they are also in the same league. I am not sure if there are other subs in this category with similar type of sound, but I have a feeling the new Mags v4's are geared towards the similar type of performance.

I will need to clear my basement from some subs before I buy the Mags. Firstly, I will need to move the 3 10" CSS SDX's, as they are too big and heavy for my application, but that was a fun project. I find it difficult to let go of my older sub projects as they are all great for their intended purposes. A single 12" DIYMA, and 2 12" Arc Audio(based of the IDQ's) are also quite amazing. Over the years, I have made some fine decisions about all my subs, and always had trouble parting, but my hobby kept calling for new exciting projects, so I always moved on. It seems though that a pair of new Mags will stay with me for the longest time, and I will do them justice and put them on an Arc Audio 2300SE. Cant wait, but I must time everything correctly.

[1sashenka]

This was a double post. I dont know how that happened.

[Tirefryr]

Was it a newer GTI or the old ones with the accordion surround?

Either way, those puppies shine sealed and are a joy to the ears run infinite baffle.

Based on your previous drivers, I don't really see you being too worried about output, and the Mag is very surprising even with low power, let alone when you can throw it's RMS at it.

[1sashenka]

It was the previous design before MKii, but it did not have the accordion surround, and from what I have been told it's pretty much the same driver. It sounded like total poo in that ported box. I just could not believe it.

[Tirefryr]

In all honesty, the enclosure was on the small side. They aren't too shabby in the proper vented enclosure, but they work so well sealed.

[Thumpper]

I have used all sizes of Wgti subs in ported and sealed....one of the best
sounding set ups I have ever heard was W10gti's ported
if you are getting distortion with a Wgti sub your install is at fault
not the woofer...
Team JBL has more trophies collected since 2003 than anyone with these woofers
I'm pushing Crown GTI power so I got MORE than enough
juice to push them to the edge of death
the only flaw with the Wgti subs is the fact JBL does not offer recone kits
but they are deadly with mucal accuracey

as far as the Xcon goes....I am running four 15's on a Crown GTI amp
and they sound awsome even in the under sized airspace I gave them
(3.50cf3 per sub tuned at 31hz)...they stay crystal clear way past the point
of my Van wanting to explode...
the power handling on them is just awsome ..hit like a mofo (under statement)

my current set up.....




the SSA Icons were a cool little project and fun to play with also.....
my Quad 10" Icon set up dropped sick low


YouTube - Picture 003


the woofer performance is reflected from the enclosure design....