Sub1500 problem

[jcdahl]

Has anyone had problems with the JBL SUB 1500s from Parts Express ?
I just recently christened mine. After about 10 hours of use, one of the SUB's spider has detached from the frame. I called PE tech support and they said they had problems with three or four units out of the 500+ units they sold in their recent inventory liquidation. Since they can not get any more, they have offered to have mine repaired at their expense by Orange County Speakers .

I wonder if this damage happened from use (I am driving them with a Mackie M2600 [800W max into 4 ohms] crossed over at 90hz and no EQ)

[Mr. Widget]

I didn't want to bring it up, but yes I have had the same problem. I bought quite a few of them. Of the first two I put into service one of mine had the exact same problem. I sent it back to PE and they quickly shipped me another. I am sure they will take care of it for you.

To put other's minds at ease, I have beat the hell out of four others with no problems. Hopefully none of those sent to Europe will be defective as the shipping issues could be a problem. If one were in a pinch I would expect it wouldn't be too difficult to re-glue the spider yourself... but I would pursue a proper repair via PE first.

Widget

[Frode]

Originally posted by Mr. Widget
I

Hopefully none of those sent to Europe will be defective as the shipping issues could be a problem.
Widget

Yeah, shipping to Norway was $150 each!

Frode

[scott fitlin]

Originally posted by Frode
Yeah, shipping to Norway was $150 each!

Frode Ouch, thats expensive freight costs!

[jcdahl]

I receive a response from Orange County Speaker repair. They say they can not re-attach the spider. They would have to recone it but they don't have parts for this speaker. They would have to substitute parts. I don't think the know which speaker this is because they kept referring to the "EON 1500" so, I will try somewhere else. Any suggestions?

[Mr. Widget]

Contact OCS and tell them you will need the C4RSUB1500 kit for your Sub 1500. They should be able to order it from JBL.

Giskard had posted the kit number on the massive Sub 1500 thread. I thought I had better take note of it for future reference. Thanks, Giskard!

Good luck,

Widget


BTW. I am sure that with care the spider could be reglued. If I were in Europe I would certainly give it a shot. OCS is saying the right thing, but then you aren't supposed to refoam a speaker either.

[jarrods]

I wonder if someone with one of the broken Sub1500's could post in a digital cam shot of the damage so I can understand what the problem looks like. I have got one of these from PE and would be very interested to know where to look to see if any damage is starting to happen.

thanks,
jarrod

[Mr. Widget]

If the woofer is out of the enclosure and you carefully push the cone forward you can see the spider lift from the frame allowing you a view of that magnificent voicecoil.

The symptoms of the failure are distortion and/or the sound of voicecoil rub. Bo happened to be at my place when it became quite obvious. It is the sort of failure that will occur by the time you have finished breaking in the woofer. Basically if it doesn't fail within the first few hard hitting hours, it won't. I suppose if you never push the thing it may never fail... remember they stress tested them to over 40Vrms for over 8 hrs. That is well over 400 rms watts continuously! Believe me you couldn't stay in the room with that!

Widget

[Tom Loizeaux]

I wonder if it would be advisable to do a pre-emptive "repair" on these Sub 1500s. It seems to me that applying extra adhesive to the spyder, forcing it down in to the fabric might keep this seperation from happening. If it's done before seperation, the spyder placement will still be correct.

Any thoughts on this from experienced JBL re-coners? Oldmics, etc.?

Tom

[jcdahl]

Thanks for the Info. I remembered the Kit being in the long SUB1500 thread but could not find it.

OC just quoted me a price of $461.00 to recone the thing with the C4RSUB1500 recone kit.

However, after I better explained the situation, they said they could probably reglue the existing spider to the frame. I think I will load it into the car and drive over to LA and talk to them. I have a couple of LE15As that need reconing and Magnet recharging anyway.


I will try to get a picture of it tonight. It is rather hard to get my camera in there.

[jcdahl]

Here are some photos of the detached spider.

It has come loose completely 360deg around the outer circumference

http://208.186.80.76/PHOTOS/sub1500/DetachedSpider.JPG


http://208.186.80.76/PHOTOS/sub1500

JCD

[Maron Horonzakz]

I guess the 1500 was'nt such a good deal after all. I wonder how many "REVEL" subwoofers have failed & were covered under warrenty?

[johnaec]

So far, I've had one Sub1500 that I'm using for live bass guitar, and two still in the box. But I run the live one at very high sustained output, probably eight hours total so far with 800 watts near max most the time. It appears fine so far - I hope the others are OK... Using them in a normal or even loud HT setup probably wouldn't drive them near as hard as my live bass, so it seems there is either a manufacturing defect or materials, (glue), defect in some of these.

How about posting SNs so we can see if only a certain run appears to be involved? I'll post my 3 later this evening or tomorrow.

John

[4313B]

Originally posted by Maron Horonzakz
I guess the 1500 was'nt such a good deal after all. I wonder how many "REVEL" subwoofers have failed & were covered under warrenty? I guess there isn't enough data yet for me to extrapolate that they weren't such a good deal after all.

[Mr. Widget]

Originally posted by Maron Horonzakz
I guess the 1500 was'nt such a good deal after all.

I am enjoying the hell out of mine!:yes:

[Tom Loizeaux]

Maybe it would be a good idea for someone with JBL connections to call the factory and alert them to this Sub 1500 problem. If JBL knows exactly what the problem is, maybe they should alert their service centers and offer a "re-call" to re-glue these spiders before damage is done to the coils.
I feel JBL would be wise to step in and take care of this if this is a wide-spread problem. JBL should value their loyal JBL users. This is an opportunity for JBL to gain statue in the marketplace!

Tom

[4313B]

I'm already on it Tom...

[jcdahl]

How about posting SNs so we can see if only a certain run appears to be involved? I'll post my 3 later this evening or tomorrow.

The defective one is number B864-005517 on it. The good one is serial # B864-05519

[scott fitlin]

Originally posted by Tom Loizeaux
Maybe it would be a good idea for someone with JBL connections to call the factory and alert them to this Sub 1500 problem. If JBL knows exactly what the problem is, maybe they should alert their service centers and offer a "re-call" to re-glue these spyders before damage is done to the coils.
I feel JBL would be wise to step in and take care of this if this is a wide-spread problem. JBL should value their loyal JBL users. This is an opportunity for JBL to gain statue in the marketplace!

Tom I agree wholeheartedly, as this isnt an ordinary driver. Its the 1500AL!

And in my honest opinion it is a problem that can be solved. They have had similar problems before, such as problems with the tinsel leads on the 2226 in the very early 90,s! They solved that, they can solve this.

[4313B]

"Sorry to hear about this. If the units are built correctly, this simply should not occur.

The spider is glued to the frame with Henkle 5019 C.A. adhesive....but, it must be applied over a PRIMER adhesive that is put on the powder coated frame to better promote adhesion of the 5019 C.A. (it is difficult for C.A. adhesive to stick to epoxy powder coating without a primer).

If production forgot to apply this primer, the spiders will pop off the frames.

You may need to re-cone, but before that I would try to wipe a primer onto the frame spider landing surface, then re-apply some 5019 CA so it soaks through the spider material.

Service centers should have 5019 C.A. adhesive, otherwise it is just a cynoacrylate..."super glue"."

[Alex Lancaster]

What primer would that be?

Alex.

[jcdahl]

This is the most FANTASTIC forum I have ever been on.

Can you imagine the poor guy that bought one of these and did not have this resource to draw on. They would be "out of luck"

You guys are Great!!!!!!!!!!!!!!!!!!!!!!!!

[4313B]

Originally posted by Alex Lancaster
What primer would that be?

Alex. I'm waiting for that specific answer.

[Tom Loizeaux]

Giskard,
Maybe you could ask this person if, since the powder coat is epoxy based, would a thin epoxy adhesive , flowed around the outer edge of the spider bond to the frame and help hold the spider in place.

Please let us know what you find out.

Thanks,

Tom

[Mr. Widget]

Henkel is the parent company of Loctite. At my model building company we use several specialty CA glues. We happen to use Loctite brand as that is what is distributed in the US to smaller end users like my company. Henkel 5019 is the same as Loctite model 422. The appropriate primer is Loctite 770 Prism Primer. I would contact Loctite to find an industrial supplier in your area that stocks these. The glue and primer together will cost about $25. This is for a rather small amount as they don't give this stuff away.

These glues do give off some nasty odors so you may want to use them outdoors, but they are quite forgiving and easy to use.

Widget

PS. Tom, I would not recommend Epoxy glue. Simply using Epoxy doesn't guarantee compatibility with the powder coating. If JBL recommends Henkel 5019/ Loctite 422, that is certainly what I would use.

[johnaec]

Originally posted by jcdahl
The defective one is number B864-005517 on it. The good one is serial # B864-05519 OK - the one that I've really pushed with no problems so far is B864-05639. The two still in the box are -05588 and -05603. I will still be a while 'til I get those going...

John

[jcdahl]

After getting a Quote from OC Speaker, Parts Express decided to undertake the repair themselves. I am sending it off today so, we will see what they come up with. I included in the returned shipment all of the good suggestions from this thread.

I'LL KEEP YOU ALL POSTED

[mrbluster]

It has been suggested to me by someone in the speaker repair business that California-built JBL speakers often have glue failures such as this. The reason being that strict California environmental regulations limit their options (for gluing) in both product and application.

I'm wondering if anyone has heard anything like this before?

[Mr. Widget]

Originally posted by mrbluster
It has been suggested to me by someone in the speaker repair business that California-built JBL speakers often have glue failures such as this. The reason being that strict California environmental regulations limit their options (for gluing) in both product and application.

I'm wondering if anyone has heard anything like this before?

I haven't. There are quite a few regulations here in California for coatings (paints and finishes) but I haven't run into issues regarding adhesives.

I expect the issue here is simply human error and someone missed applying primer to a few woofers or they got behind schedule. There is a specified open time for the primer. If you don't apply the adhesive within the appropriate time window after application of the primer the adhesion will be compromised.

As for an issue with all JBL woofers... they are abused all over the world in live venues and theaters, I doubt they could stay in business if they were constantly running into failures of this type. So far based on the info from PE the failure rate of this lot of Sub 1500s is on the order of 1%. I doubt even that low number is acceptable to JBL.

Widget

[scott fitlin]

Enviromental codes have changed dramatically all over the country! Paints, solvents, and adhesives are not formulated with the same chemicals they were ten years ago. If this is in fact the problem, JBL WILL come up with a solution that works. They have had problems here and there with various drivers and have always fixed the problems! I dont really see this as something that cant be fixed!

[jbl]

Where all of the defective 1500's purchased at Parts Express?

[jcdahl]

Originally posted by jbl
Where all of the defective 1500's purchased at Parts Express?

Mine was... They are working on it now.

[scott fitlin]

If worse comes to worse, and they cant rectify the situation, PE could always give you guys a few Genuine Eminence drivers, after all, IF youve listened to live music, chances are youve listened to Eminence!

:duck:

[Zilch]

O.K., so tell me why sending them SUB 1500's back to JBL for warranty repair is not an option?

I have four I haven't fired up yet.

[Working on it, tho....] ;)

[johnaec]

I doubt JBL directly warrants these particular Sub1500s because they apparently were intended for use in the Revel subwoofers, and this stock was either discontinued/surplus, and not intended for end users as individual components.

If you actually had one of the Revel systems, maybe JBL would accomodate you, unless they directly supply Revel with recone kits, but as far as I know, "gray market" items like these are rarely covered by the manufacturer, especially at the price they went for. They *might* do a recone at the factory, (does JBL still do that?), but I doubt it would be covered by warranty...

John

[MJC]

Originally posted by jcdahl
After getting a Quote from OC Speaker, Parts Express decided to undertake the repair themselves. I am sending it off today so, we will see what they come up with. I included in the returned shipment all of the good suggestions from this thread.

I'LL KEEP YOU ALL POSTED

Selling speakers and other parts is one thing, but doing speaker repair is a whole different animal. I realize that we paid only $250 for these and OCS repair prices aren't cheap($200 for 112A recone). So the question becomes how good of a job will PE do? Hopefully for those with this problem, a job comparable to OCS.

[Hofmannhp]

Hi All non functional sub 1500 users,

someone has please to explain me what's about the guarantee of the company (mostly with 5 years for fabricational disfunctions)
I can not understand, why the owners of such new speakers not easy ship them back and get a new.

:confused:

HP

[Zilch]

I don't care who the "Dealer" is, JBL Pro typically warrants its products against manufacturing defects, and provides excellent factory service.

This is clearly defective manufacturing, and, unless there was a specific warranty disclaimer, we should be leaning on the factory to take care of it directly.

Do we presume "Tent Sale" or "B-Stock" items come without warranty just because we get a good deal on them?

[Robh3606]

As far as I know all items from the Tent are under waranty. I got damaged goods that were promptly replaced. Now with parts sold through PE?? If it was a close out of 2226's they would be covered against defects in workmanship. So why not these??? Unless the intention was not to sell them as drivers. Bottom line is has anyone actually contact JBL to find out??

Rob:)

[Mr. Widget]

It seems that there is a lot being made about very little here.

These woofers were sold by JBL at well below their normal wholesale cost. PE was able to purchase JBL's remaining inventory for a song and they passed it on to us. PE is in effect offering the warranty. JBL might take care of these speakers, but since they dumped them they certainly are not obligated to. I am sure if PE can't fix them, they will refund the money paid for the woofers. That would be the "right" thing to do and they are a very ethical company.

If I end up having a problem with any of the remaining woofers that I have yet to unbox I think I would fix it/them myself. It is a simple fix. Since Giskard sleuthed the proper glue, it would be easy for any of us to do the repair.

Why are so many people so uptight about such a simple problem that has only affected a handful of woofers?

Widget

[Zilch]

... it would be easy for any of us to do the repair.

Heh, heh. If any of mine fail, I know who to call now. ;)

[4313B]

Originally posted by Mr. Widget
Since Giskard sleuthed the proper glue, it would be easy for any of us to do the repair.Yes, I would think a physical check of the spider and spider pad would indicate an imminent failure. If the spider is easily separated from the pad then careful application of primer and glue is in order. I would be inclined to repair small sections of the spider so as to keep the voice coil properly aligned. I've seen this happen on other drivers before. 115H-1's and 127H-1's come to mind. The spider will separate pretty easily if the primer was forgotten. Like the designer of this driver said - it should never fail if the primer was applied first.

*****

What are the over-the-counter primer and adhesive equivalents Mr. Widget?

[Don C]

I don't think that we want to make a big fuss about this. Problems like this might make JBL want to bury the next batch of surplus woofers in a landfill anstead of selling them off so cheaply.

[4313B]

:rotfl:

There just might be some merit in that! Harman sure had no problems filling several huge dumpsters with perfectly good service product back in the nineties! Dark days indeed! Never even offered the Service Centers the opportunity to stock up for their hard won customers!

[Mr. Widget]

Originally posted by Giskard

What are the over-the-counter primer and adhesive equivalents Mr. Widget?

The glue is Loctite model 422. The appropriate primer is Loctite 770 Prism Primer. We buy Loctite products from R.S. Hughes Co. They stock the full line of Loctite products and have offices all over the country. Their toll free number is 877-774-8443

The smallest amount they stock is a 1 oz. bottle. That will do dozens and dozens of woofers. I called and the 422 was just under $20. I didn't price the primer. I have some that I use with other Loctite CA glues. I would expect it to be in the $10 range.

Widget

[mrbluster]

Would someone care to describe the proper procedure and or technique ?

[Mr. Widget]

Originally posted by Giskard
.... wipe a primer onto the frame spider landing surface, then re-apply some 5019 CA so it soaks through the spider material.

Service centers should have 5019 C.A. adhesive, otherwise it is just a cynoacrylate..."super glue"."


Here are the directions that Giskard posted earlier in this thread. The Loctite version of the glue comes in a squeeze bottle with an applicator tip.

After you order the glue ask Loctite or the distributor for application information so that you know the flash and open times for the primer.

Widget

[mrbluster]

Any cleaning, sanding or other prep of Landing surface before primer?

[Mr. Widget]

They are brand new and should be clean. The spider is glued directly to the powder coat finish.

Do you have a defective woofer?

Widget

[mrbluster]

My SUB1500 is still on the shelf, I am afraid that by the time I put it to use, If there is a problem, my options will be limited (Don't know how long PE will stand behind these?) It would be reasuring to know that I could handle the repair in the event it was needed. My thinking regarding the preping of the surface was with the idea that some of the old bonding material might remain.
Thanks Widget,

MB

[jbl]

What ever happened to JBL's claim on all their spec sheets of raw drivers that if the driver didn't meet spec it was destroyed? It is a big mistake for JBL to let anything go on the market with such a high defect percentage. If they are selling their defects to parts distributors, they (JBL) will ruin their reputation in no time.

Ron

[mrbluster]

It would be nice if both Parts Express and JBL would issue a clear statement outlining there position on this problem including options and time frame. Although it might be reasuring to have Information for a "Do it your self" repair, It is really not an appropriate solution considering the circumstances.

MB

[4313B]

I think you should probably start with PE and see where they got the drivers from.

*****

Where is the data showing the defect percentage? I can't find it.

*****

Check the PE forum to see if there are any 1500SUB issues on it.

[Mr. Widget]

Ron,

I agree that JBL shouldn't sell their rejects. That said, I doubt that these woofers were seconds or rejects. So far we have run into two failures out of the several dozen that were purchased by forum members. This is unfortunate, but sometimes people make mistakes. I for one am glad that JBL sold these surplus woofers to PE so that we would have the opportunity to enjoy them at a very small fraction of their retail price.

Since these woofers were not sold at retail I don't think JBL is obligated to do anything. One reason that a new JBL or any other product costs what it does is that part of that price is to cover the occasional replacement or warranty repair that is inevitable. As a quality retailer PE will take care of any problems that may arise.


Widget

[jcdahl]

My guess is that PE did not get these from JBL. They probably bought them from an "excess Inventory" liquidator in Europe. Most often the original manufacturer's warranty would not apply to this kind of merchandise. Personally, I dont think this is a serious problem. I am sure PE will provide service to these drivers if more incidents occur of this nature. I have talked to them just last friday and they assured me they will be able to repair mine and it will be "good as new". It should be on its way back to me next week. I'll keep you all posted.

[jbl]

Mr. Widget,
I agree. Both JBL and PE should be allowed to correct the problem. If it is a problem. I was unaware that so few units were affected. Assuming that these units were in some way "rejects" was unfair.

Ron

[Tom Loizeaux]

It was pointed out to me that, because the Sub1500 has breather holes punched throught the cone, between the inside of the dust cover/ voice coil area, that dirt and debris might be sucked into the gap. All the other JBL cone drivers I have seen use screens to keep out debris, but the Sub1500 does not! I wonder what JBL would say about this?

If I decide to keep mine, I think I will glue small discs of a very fine mesh (sheer stocking) over these holes.

Tom

[johnaec]

Originally posted by Tom Loizeaux
It was pointed out to me that, because the Sub1500 has breather holes punched throught the cone, between the inside of the dust cover/ voice coil area, that dirt and debris might be sucked into the gap. All the other JBL cone drivers I have seen use screens to keep out debris, but the Sub1500 does not! I wonder what JBL would say about this?

Tom JBL is usually pretty conscientous about this kind of stuff. I wonder if it's really open to the voice coil gap under there, or if they addressed it somehow, though I don't know how they would do it.

Interesting... :hmm:

John

[jcdahl]

Well, at long last, I have received my repaired SUB1500 back from Parts Express. It works great and looks as good as new.
They explained that the reason it took so long was that they did not repair it in-house. They sent it out and the shop they sent it to had to order special adhesives and primer to ensure that the job was done right.

It looks like the did the job right.

WOW! Two of them really do the job. I have been running them with my Paragon and I hear things that I never knew were on the some of my CDs. Really Low and really clean bass.

I am building some companion speakers for them using a pair of LE10's to cover 90HZ to 500HZ, a pair of LE5-6's to cover 500 to 7000 and a pair of 075's to fill in the top

Iwilll tri-amp the system using my Makie 2600 to drive the SUBs and a Dynaco ST70 to drive the LE10 and Le5's, and a JBL solid state 20W amp to drive the 075's Crossover is accomplished with a Rane three way electronic crossover and the Mackie built in 90HZ crossover

[maxwedge]

The glue is Loctite model 422. The appropriate primer is Loctite 770 Prism Primer. We buy Loctite products from R.S. Hughes Co. They stock the full line of Loctite products and have offices all over the country. Their toll free number is 877-774-8443

The smallest amount they stock is a 1 oz. bottle. That will do dozens and dozens of woofers. I called and the 422 was just under $20. I didn't price the primer. I have some that I use with other Loctite CA glues. I would expect it to be in the $10 range.

Widget
Thanks for the tip to R.S. Hughs.:)

I had one of my sub1500's spiders lift from the frame as well.:( I was drunk one night and was trying to get one of my pc's to output into my system and it wasn't working.:( So then I hit some button and there was sound, with everything maxed out, but I couldn't pull the siders down fast enough on my board. Sounded like alliens were landing!!:applaud:

I have 2 sub1500's in a single 5 cu ft sealed box powered by a QSC rmx2450 amp. 1 failed and the other is ok. The failed serial # is J864-05990, if anyone is keeping track.:blink:

[toddalin]

JBL is usually pretty conscientous about this kind of stuff. I wonder if it's really open to the voice coil gap under there, or if they addressed it somehow, though I don't know how they would do it.

Interesting... :hmm:

John

The W15GTI also has no screen..., just a massive hole up to the cone area.

[andresohc]

Yeah, and given the expected environment is a car trunk its kinda scary:blink:
The W15GTI also has no screen..., just a massive hole up to the cone area.

[jarrods]

Listening to a very bassy track (Janet Jackson - Together Again) at a moderate levels and started to note a bit of a flutter sound from my left sub. Pulled the driver out and the spider has detached about 1/3 of the way around. Looks like a simple fix as it is very easy to get to but I have just emailed PartsExpress to see how they want to tackle it.

Jarrod

[4313B]

I wonder just how many warranty claims JBL has had against these drivers as used in the Revel 15, HB1500 and TiK.

I didn't realize the driver was that old but it looks like it was in R & D in 1997.

I do not see a nice clean bare aluminum pad where that spider is supposed to attach Jarrod. It looks to me like it's glued to krinkle paint with Bostik.

[Mr. Widget]

I have had one failure out of six that I have put in use. My failure looked like Jarrods, with a very clean separation. Some of the Sub1500s that I own have a very messy looking glue line around the edge of the spider. I am not sure if this was in response to the failing glue jobs or if mine are factory reconditioned units.

Jarrods, since shipping the drivers back to PE or JBL will be quite costly, you should track down the correct Loctite or Henkle glue and primer. Look at posts 20 and 25 in this thread.

http://audioheritage.org/vbulletin/showthread.php?p=22690


Widget

[jarrods]

Yes it is glued to the grey krinkle paint and the glue is a dark yellow colour.

I thought the consensus was that JBL used a Loctite 422 glue over a 770 primer for these units. Would be a bit of a worry if someone on the floor thought to themselves "I think i'll use a bit of Bostik instead of superglue today".

Maybe the home-fix will not be as easy as I thought if I need to remove the Bostik and krinkle paint.

jarrod

[John]

For the price you guys got those for and considering what they can do, just fix them and be happy. :applaud:

[Mr. Widget]

Maybe the home-fix will not be as easy as I thought if I need to remove the Bostik and krinkle paint.Based on the ugly over glued units I have, I would refrain from cleaning as you'll likely get junk in the gap. I'd spray the primer on the metal (wrinkle paint) and then soak the hell out of the edge of the spider and 4mm or so down the side of the frame with glue and I'd expect you'd be good to go. At least that is how some of mine look.

Widget

[jarrods]

The response to my question of Loctite Australia about the products was not what I wanted to hear:

"Thank you for your query.
422 is a gap filling Instant Adhesive (up to 0.02").
The 422 is brought into Australia in the 500g packaging only. There is no smaller size available."

Now that would be good if I had 1,000 failed drivers. Let's see what PE want to do? Maybe they can send me some glue & primer. :D

jarrod

[maxwedge]

In my 1st post in this thread, http://www.audioheritage.org/vbulletin/showpost.php?p=82274&postcount=60, I said only one of my sub1500's had failed. I was wrong....both did.:( But not to the same degree. The 1st failed around 3/4 of the diameter of the spyder while the 2nd only 1/3.

My repair method on the 1st didn't quite turn out 100% good because at loud volumes the voice coil rubs now, so it appears it shifted when I glued it down. I believe I lifted the spyder too high because there's not much room too squease that glue in from the side. I did run a 30hz signal through it then and it was ok but the next day it was rubbing.:( I'm hopeing it will loosen up over time.:dont-know

On the 2nd driver I figured out how to get the glue in there with out screwing up!:applaud:
Tilt the sub1500 on it's edge, and get some help because it's heavy, lift that spyder just a little with a knife, dribble the glue in the gap and rotate the speaker on it's edge as you go. See now it's easy with the glue bottle vertical!:banghead:

PS: The 1st pic shows the only spot where the spyder didn't lift. I used cloths pins to hold it up.

[4313B]

For the price you guys got those for and considering what they can do, just fix them and be happy. :applaud:I think that's what people are trying to do. The designer of the transducer was shocked that these drivers weren't being manufactured correctly.

[jarrods]

Parts Express will not entertain a warranty as they say it is from a 'buyout'. JBL Professional aren't interested as they have no records of a SUB1500 driver ever existing. Even when I say it sits here in a box clearly barcode labelled as model SUB1500 right next to a big white JBL Professional sicker they still say it is not their product. OK so it might be JBL Consumer but why is it packed in a box of another company/division.

Anyway I have ordered some 770 and 422 from R.S.Hughes in 50ml and 30ml sizes repectively. Better than what is available here in Australia the 500ml bottles...

jarrod

[maxwedge]

1 Sub1500 dead (the one above in the pic's) and my other on it's way out.
Have some graphic pics to post. The spider totally detached from the cone!:(

I'm seriously doubting that it's worth repairing these things. :dont-know::(

[maxwedge]

At least my glue job didn't fail!:)

I'm holding the cone up with my thumb.:(
http://i76.photobucket.com/albums/j7/maxwedge572/Music%20Gear/My%20Sound%20System/Detachedcone.jpg

[Mr. Widget]

1 Sub1500 dead (the one above in the pic's) and my other on it's way out.
Have some graphic pics to post. The spider totally detached from the cone!:(Seems as though you need more woofer... either more than one pair of Sub1500s, or simply more woofer. Personally I do not like the sound of the 2242 as much as I like the Sub1500 or W1500H, but they are nearly indestructible. In addition to having a different sound, they also require much bigger boxes.


Widget

[Eaulive]

Seems as though you need more woofer... either more than one pair of Sub1500s, or simply more woofer. Personally I do not like the sound of the 2242 as much as I like the Sub1500 or W1500H, but they are nearly indestructible. In addition to having a different sound, they also require much bigger boxes.


Widget

The problem with smaller boxes is the higher excursion needed from the the woofer. This is a likely cause of failure.

[4313B]

What a shame.

How hard were you driving them?

[maxwedge]

I pulled out my other Sub1500 and it's spider is separating from the cone as well.
BUT, the spider has not ripped. The glue bead has detached from the surface of the spider and I can clearly see that the spider is not damaged at all.

Bummer, my bottle of 422 Loctite is hard as a rock so I guess it's shelve life is well under 6 years. :D I'm going to order some more and try and fix this one Sub1500.


Seems as though you need more woofer... either more than one pair of Sub1500s, or simply more woofer. Personally I do not like the sound of the 2242 as much as I like the Sub1500 or W1500H, but they are nearly indestructible. In addition to having a different sound, they also require much bigger boxes.


Widget
No more room for additional speaker boxes in my living room. I have 4 more 18's stored but can't do it. I like the Sub1500 better for HT as well.

[maxwedge]

What a shame.

How hard were you driving them?
I have to admit that the failures on these two were most likely my fault. :o:
see my quote from 2005 below. That amp puts out around 1300-1500 watts bridged into the 2 Sub1500's



Thanks for the tip to R.S. Hughs.:)

I had one of my sub1500's spiders lift from the frame as well.:( I was drunk one night and was trying to get one of my pc's to output into my system and it wasn't working.:( So then I hit some button and there was sound, with everything maxed out, but I couldn't pull the sliders down fast enough on my board. Sounded like aliens were landing!!:applaud:

I have 2 sub1500's in a single 5 cu ft sealed box powered by a QSC rmx2450 amp. 1 failed and the other is ok. The failed serial # is J864-05990, if anyone is keeping track.:blink:

[JeffW]

Bummer, my bottle of 422 Loctite is hard as a rock so I guess it's shelve life is well under 6 years. .

I keep all my various Loctites and CA (Super) glues in the fridge, it greatly extends the shelf life. Just be sure to let it come up to room temp before you open it or you can get condensation on the inside of the bottle which is especially bad for CA.

[toddalin]

I have to admit that the failures on these two were most likely my fault. :o:
see my quote from 2005 below. That amp puts out around 1300-1500 watts bridged into the 2 Sub1500's


Seem like the power level should not be an issue so long as they weren't bottoming out or over-excursioning, which you should have heard.

[Mr. Widget]

Seem like the power level should not be an issue so long as they weren't bottoming out or over-excursioning, which you should have heard.:blink:
He ripped the coils off of the cones! That means they were trying to exceed xmax... as you must know these things are thunderously loud at high power levels. It can be hard to tell if that god awful racket is the cone tearing or your house protesting as the drywall is bending and flexing, the floor creaking, windows and doors rattling etc.


I have to admit that the failures on these two were most likely my fault. :o:
see my quote from 2005 below. That amp puts out around 1300-1500 watts bridged into the 2 Sub1500'sOn a tangential subject... a single bridged amp running a pair of 4 ohm speakers? Is your amp stable into 2 ohms when bridged? Almost none are. Or did you wire the pair in series so that your amp saw an 8 ohm load?


Widget

[Eaulive]

Or did you wire the pair in series so that your amp saw an 8 ohm load?


Widget

Which is basically the same as running one independently on each channel.

[1audiohack]

Two of the six of mine have that opaque glue on the spider / cone / former junction and what ever it is, it does not penetrate the pourus materials at all, it sits on top like hot glue would and does not give a buttressed joint at all. You just know without some kind of rework it's going to fail and that sucks!

[JBL 4645]

What a shame.

How hard were you driving them?

I think! Its the unnecessary power that was being used to not only hear the tones but feel them as it should be in an ideal situation where frequency response is smooth and both uniform over the seating area.

Common failure is not seeing what the frequency response is like against the LCRS or LCR where it should only tickly the bottom end where LCR hands it over to sub should be at the same frequency response with minimal power being used up.

Start running it without realizing you have sloping frequency dip starting at such and such frequency covering several bands then rising up to smooth with peak or two. But its that tone that tells the user something missing or maybe its not loud enough!?

If you looked the internal frequency against the in-room its miles apart if for some good reason it mirrors what it is on RTA or spectrum lab then with all fairness you hit the jackpot.

The sub as it is, is playing super fine its when you move away from Mr Null sigh I wish there was an anti-spray for this issue. Only way around it is more of the same sub to counterattack the issue and yes up goes the cost for that narrow band limited LFE.1 channel that seems to be the biggest pain the home cinema ass to get truly sorted!

Boast the issue on the sub is like the death sentence for the sub it will limit the headroom and place critical clipping and bottoming out before you’ve had chance to get a few years enjoyment out of it.

As for other mechanical workings of the sub that’s down to lousy cheap craftsmanship and we should go after them with soldering iron.:D

[grumpy]

Easy to overdo xmax if 1) you're not running a sealed box, 2) are playing
content below system resonance (which one might tend to do showing these off),
but yeah... kind of like running low on air in a 40-series tire (difficult to tell until
it's too late).

[maxwedge]

:blink:
He ripped the coils off of the cones! That means they were trying to exceed xmax... as you must know these things are thunderously loud at high power levels. It can be hard to tell if that god awful racket is the cone tearing or your house protesting as the drywall is bending and flexing, the floor creaking, windows and doors rattling etc.

On a tangential subject... a single bridged amp running a pair of 4 ohm speakers? Is your amp stable into 2 ohms when bridged? Almost none are. Or did you wire the pair in series so that your amp saw an 8 ohm load?


Widget
Series for 8 ohms.:yes:
I think that the amp was most likely clipping that night but I was too busy grabbing for the sliders on my mixing board to look.:crying:

[Eaulive]

Series for 8 ohms.:yes:
I think that the amp was most likely clipping that night but I was too busy grabbing for the sliders on my mixing board to look.:crying:

You know that you gain nothing from doing this? A stereo amp with a 4 ohms load per channel or an 8 ohms load in bridge mono is exactly the same thing, both for the amp and the speakers.

It doesn't hurt anything however, it's just the same. :)

[JBL 4645]

The one thing these active subs don’t have on them is a barograph LED level display so you know when to back it down once that clipping LED lights up!

[maxwedge]

You know that you gain nothing from doing this? A stereo amp with a 4 ohms load per channel or an 8 ohms load in bridge mono is exactly the same thing, both for the amp and the speakers.

It doesn't hurt anything however, it's just the same. :)
Yes you gain something running bridged. One xlr cable and power cable each to be used elsewhere.:p

[Eaulive]

Yes you gain something running bridged. One xlr cable and power cable each to be used elsewhere.:p

Right! Can't argue with that :D

[toddalin]

:blink:
He ripped the coils off of the cones! That means they were trying to exceed xmax... as you must know these things are thunderously loud at high power levels. It can be hard to tell if that god awful racket is the cone tearing or your house protesting as the drywall is bending and flexing, the floor creaking, windows and doors rattling etc.

Widget


Or perhaps everything was within the max excursion limitations until the spider pulled away, then all he11 broke loose.

[maxwedge]

Or perhaps everything was within the max excursion limitations until the spider pulled away, then all he11 broke loose.
This separation of the cone and spider is not new.
http://www.audioheritage.org/vbulletin/showthread.php?8281

[toddalin]

This separation of the cone and spider is not new.
http://www.audioheritage.org/vbulletin/showthread.php?8281


I understand that the separation issue is not new.

I'm just saying that perhaps your voice coil didn't jump out out the gap until the spider separation occured and that the occurance may have happened within the normal xmax limits. When the spider lets go, there is less tension holding the coil in the gap so it can jump out at less than the speced xmax input.

I've always had the cones slap the magnets with an audible "thunk" before a cone gets far enough out of the gap on AlNiCo JBLs and the W15GTi takes it all in stride without a complaint.

[maxwedge]

I'm just saying that perhaps your voice coil didn't jump out out the gap until the spider separation occured and that the occurance may have happened within the normal xmax limits. When the spider lets go, there is less tension holding the coil in the gap so it can jump out at less than the speced xmax input.


I agree with you and I believe that damage that happened with my 2 sub1500's is a combination of user abuse, intentional or not:o:, and defects in the gluing of the spider.

To recap: in 2005 these went from Idle to max power instantly (can't remember the program type, most likely a sine wave signal) with 1500 watts. Grabbed the sliders on the mixing board as fast as I could and pulled them down. After that I had lots of voice coil rub at low volumes in one of the subs (the one in the pics here). I pulled this speaker out and found that the spider was loose from the basket a bit more that 3/4 the dia.

I glued that spider down and inspected the other sub. The 2nd spider only lifted about 1/4 the dia max.

Reinstalled them and tested. The 1st sub1500 had some minor vc rub (I know, not acceptable!) at higher volumes and the 2nd one had no noise. I figured I didn't get the spider correct on the 1st and decided to live with it until it got worse.

Fast forward to 2010-11 and I got this new Marantz Pro-pre that has a much better subwoofer decoding that my old Yamaha. I was viewing Tron Legacy in Blu-Ray and the Lightcycle scene has some massive sub action. That 1st sub1500 came apart again in that scene.

I pulled it out and that's what you see in those pics of mine. My prior repair hadn't failed.
My other one is failing in the same manner but it hasn't ripped out like the 1st so I got some new super glue and I'm going to try to repair it but ultimately I will recone them as long as I can get the kits.

[maxwedge]

I gave it a shot this morning on my other Sub-1500. The 1st one has an open-circuit.:(
Didn't feel like waiting on an order for some Loctite 422 so I went down to a local auto body supply store and picked up a similar product by 3M. I'm going away this week end so I'm not going to be able to test it much. 3M says 12-24 hours for max strength.

I used some Bamboo skewers to hold open the gap, sprayed the primer in, let I sit a little and then used a syringe to apply the Cyanoacrylate adhesive pulling the skewers out as I went around.

The area around the leads separated from the cone and the rest from the spider.
the spider is not torn at all.
http://i76.photobucket.com/albums/j7/maxwedge572/Music%20Gear/My%20Sound%20System/Conetear.jpg

http://i76.photobucket.com/albums/j7/maxwedge572/Music%20Gear/My%20Sound%20System/Skewers.jpg
In the pic below look in the center of the glue bead and you see a crack in the original glue.
There are many of these cracks in the glue beads on both speakers.
http://i76.photobucket.com/albums/j7/maxwedge572/Music%20Gear/My%20Sound%20System/CrackinGlueBead.jpg
The syringe came from one of those sinus kits for spraying a solution up the nose!:p:D
http://i76.photobucket.com/albums/j7/maxwedge572/Music%20Gear/My%20Sound%20System/Adhesive.jpg

[grumpy]

Here's to hoping it holds better than the original :cheers:
...sure looked like a pure adhesive failure (too brittle for the application?)

[maxwedge]

Here's to hoping it holds better than the original :cheers:
...sure looked like a pure adhesive failure (too brittle for the application?)
Thanks grumpy. Yes it looks very brittle and there's no way I can remove the original adhesive.

I applied the adhesive around 10am and it still hasn't cured and according to this article I quote here, I need to go do some heavy breathing on my speaker!:D:p


Cyanoacrylate glue is the technical term for glues with brand names like Crazy Glue, Super Glue or Insta-Bond. It is a catch-all term for quick bonding super glues that are used in fixing or combining plastics to other materials like wood or metal.
Cyanoacrylate glue is an acrylic resin, which is vastly different from the traditional adhesives like water based glues. An acrylic resin would usually be composed of two different and separate liquids -- one that is poured into the mold, while the other is used sparingly for the purpose of making it a hardener. In cyanoacrylate glues, the hardener that is used is water.
The main ingredient in cyanoacrylate is, of course, cyanoacrylate. This type of glue, if placed on a dry surface or on certain plastics will not form a bond with the surface. But if the slightest amount of water is introduced – and this includes moisture from the air – the molecules of the glue will undergo a chemical reaction and form a tight chain between the two surfaces that will be bonded. This chemical reaction will happen seconds after the water and cyanoacrylate come into contact. Traditional glues will depend on evaporation to form a bond. But a cyanoacrylate glue will actually generate heat to help in the curing process.
There are some users of cyanoacrylate glue that get frustrated because they can’t achieve a bond that they need. But this happens if there is a lack of moisture or if the materials are non porous. A thin layer of water introduced to the bond, or even breathing on the material may introduce enough moisture to produce a stronger bond.

[maxwedge]

The SUB1500 I just tried to repair still has issues.
At low volumes there are no problems at all but in extreme LFE sections of movies it sounds like the voice coil (former?) is bottoming out. I've pulled it out and rechecked my glue job and it is holding. I used one section of the movie Tron to set the sub level and I had to back down the level on my Marantz to the max, -12db, and back down the sensitivity on the amp quite a bit to the point where the speaker stops acting up.

So I'm in limp mode...:crying:

Anyway, can someone in the repair profession tell me if the kits are are available?
The number is C4RSUB1500

Thanks
Scott

[4313B]

Yes, they are available. You might want to contact Edgewound and see if he'll recone it for you.

[maxwedge]

Thank you for that info and I would love to use Edgewound but he's a long ways from me so
I was planing on using Daniel at AUDIVEX in Berkeley. He tried to find some info on the kit but couldn't find anything and then I called up JBL Consumer and that was some joke! The guy at JBL had no clue and sounded like he didn't even want to bother to figure out how to get the kit!:(

[rdgrimes]

The phone techs at JBL Pro are much more smarter and easier to deal with. ;)

[Mr. Widget]

Thank you for that info and I would love to use Edgewound but he's a long ways from me so
I was planing on using Daniel at AUDIVEX in Berkeley. He tried to find some info on the kit but couldn't find anything and then I called up JBL Consumer and that was some joke! The guy at JBL had no clue and sounded like he didn't even want to bother to figure out how to get the kit!:(I would second 4313B's suggestion. Sometime back Zilch asked Daniel to help out with a blown Sub1500... he couldn't get the kit. Edge called his contacts at JBL and was successful I believe.


Widget

[maxwedge]

The phone techs at JBL Pro are much more smarter and easier to deal with. ;) Yeah but the Sub1500 is a consumer department product (spec dept) as I understand so that is why I called them.

[maxwedge]

I would second 4313B's suggestion. Sometime back Zilch asked Daniel to help out with a blown Sub1500... he couldn't get the kit. Edge called his contacts at JBL and was successful I believe.


Widget
Alright, looks like I'll need to plan a trip to Disneyland to keep the family happy.:D

[rdgrimes]

Yeah but the Sub1500 is a consumer department product (spec dept) as I understand so that is why I called them.
Makes no difference, they have access to all the same parts.

[1audiohack]

Makes no difference, they have access to all the same parts.

That's not always the case.

[Earl K]

5 - 7 yr old info ;




Thanks for the Info. I remembered the Kit being in the long SUB1500 thread but could not find it.

OC just quoted me a price of $461.00 to recone the thing with the C4RSUB1500 recone kit.

However, after I better explained the situation, they said they could probably re-glue the existing spider to the frame. I think I will load it into the car and drive over to LA and talk to them. I have a couple of LE15As that need reconing and Magnet recharging anyway.


I found out today that the recone kit, part number C4RSUB1500, is $223.97 (dealer cost). The JBL service place says "that's typical of JBL Consumer - they charge 3 times as much as JBL Pro". The JBL service technician said he charges $40 labor for a recone, and will not do the job using the C4RSUB1500 for fear of screwing up and being responsible for replacing the recone kit. :(


Standby for "Sticker Shock" .:eek:

Personally, I wouldn't give up quite yet ,,, I'd see if someone in your area ( talented in reconing ) can rebuild those woofers from their existing parts // assuming you haven't yet totaled the voice-coils.

OTOH; might be time to file under ; Shoulda, Woulda, Coulda !:dont-know:

<> EarlK

[maxwedge]

Sticker shock no kidding, especially that those are 2004 prices!:eek:
Shoulda, Woulda, Coulda is right, I had my chance back in 2005.:o:



Personally, I wouldn't give up quite yet ,,, I'd see if someone in your area ( talented in reconing ) can rebuild those woofers from their existing parts // assuming you haven't yet totaled the voice-coils.
That is what Daniel at Audivex suggested. I know that the coil on the one I just messed with is ok but the other one is open. He said that most likely that the cone scraped the coil on the open one and said that he'd have to get the baskets down to bare metal to see if they could be repaired with out reconing.

I've been looking for reasonably priced replacements and there's not much out there.
The TC Sounds LMS-R 15 looks interesting at $433. http://www.parts-express.com/pe/showdetl.cfm?Partnumber=293-662
I hate having broken parts laying around though.

Scott

[Earl K]

http://www.audioheritage.org/vbulletin/attachment.php?attachmentid=2054&stc=1&d=1077326148


That is what Daniel at Audivex suggested. I know that the coil on the one I just messed with is ok but the other one is open.,,,,,,,,snip,,,,,,

Maybe Daniel can source an aftermarket voice-coil ( to graft onto your cone & existing spider ) .

The above specs will give any reconer an idea of what to look for & where to match .

It's a long shot( to find a single 4" coil this long , at 1.78" ), still,, it's worth a mention .

<> EarlK

[maxwedge]

Thats the plan. I'm going to take them over Audivex next Friday to see if they can be rescued and in the mean time I'm going to make some calls to see what a full recone will set me back.;)

Thanks Earl

[maxwedge]

The good news, I snagged two unused Sub1500's for a reasonable price on ebay. $305 for the 1st and $381 for the 2nd plus shipping and their clearly unused in the original boxes with partsexpress shipping labels to the original buyer (same as seller).

The 1st one showed up Friday (2nd comes Tuesday) and I swapped it with my semi function speaker. It's in a 5cf sealed box powered by one channel of my QSC RMX2400 that's about 750 watts at full output per channel.

It's been fine listening to music and movies on DTV. Today I recalibrated my system using the Audyssey setup on my Marantz AV7005 and it sets the sub at -9db which is typical for my 7.1 system. My lowest output speakers in the rear are set close to 0db.

So I decided to test the sub afterwards with the Lightcycle scene in Tron Legacy (Bluray) again.

The bad news. Wthin 5 seconds into this movie I heard the dreaded crackle and I shut the amp off. Now Audyssey sets the system up at 0db output and I generally watch Bluray movies at about -10. I pulled the speaker out and found that the spider has completely blown off of the basket. Bummer...........................:(:o:

I was going to try another brand but then....

[maxwedge]

My 2nd new sub1500 came into today and I was just going to put it on the shelf for awhile while I figure this problem out but then what the hell I thought!:banghead:

F**k it, if it blows it blows! Put it in my sealed 2x15 cab with the sub1500 I fixed and wired them for 8 ohms. Babying it with only one side of my RMX2450 for now at ~500 watts.
Not going to push them until I get the other two fixed.

[Mr. Widget]

Babying it with only one side of my RMX2450 for now at ~500 watts.
Not going to push them until I get the other two fixed.If you look at post 110 above these things are meant to fail at a bit above 500 watts. Is it possible that you are simply blowing them up because you need more than they can put out at ~500 watts?


Widget

[maxwedge]

If you look at post 110 above these things are meant to fail at a bit above 500 watts. Is it possible that you are simply blowing them up because you need more than they can put out at ~500 watts?


Widget
35vrms is about 500 watts? The LE-1 amp used with the Revel sub output 700 watts minimum in to a single sub so I shouldn't be out of line.

Actually I misstated the output of my amp, it's 450 per ch into 8 ohms and 650 per ch watts into 4 ohms, FTC sweep 20hz-20k hz. So right now I safely doing ~450 watts for 2 sub1500's. The one I blew on Friday was connected as 650 watts but there was no way it was seeing that because my Marantz set the sub down to -9db in relation to all the other speakers. I don't know, it's the damn LFE in movies that is doing it!:D

[4313B]

You might want to measure the Qtc of the driver in the sealed box and make sure you have enough restoring force. If there isn't any the driver will blow up.

If the box is too big for a sealed solution you might want to port it and then apply a high pass filter at the box tuning frequency. That will increase VLF sensitivity considerably and you can back off the power a bit.

These drivers should barely move before they start busting stuff up in your house. If you're getting anywhere near xMech then you might have a serious node problem in your room. Load the boxes up in some corners and see if that makes the problem go away.

I use a 200 WPC Citation 22 that is capable of dumping 120 amps of current when needed and there isn't any problem driving these monsters to unbearable levels. My room is fairly small though.

[Mr. Widget]

35vrms is about 500 watts? The LE-1 amp used with the Revel sub output 700 watts minimum in to a single sub so I shouldn't be out of line.35vrms is ~300 watts @ 4 ohms... your Revel LE-1 amp comparison doesn't take into account any infrasonic filtering Revel may have used in that design.

I second the concern about the Qtc of the 5 cu ft sealed box... I have never used anything larger than about 3 cu ft, except when using them in a ported configuration... you do get almost 10dB greater output when going ported with a 5 cu ft box tuned to 20Hz, but then you MUST filter below 20Hz.


Widget

[maxwedge]

You might want to measure the Qtc of the driver in the sealed box and make sure you have enough restoring force. If there isn't any the driver will blow up.

If the box is too big for a sealed solution you might want to port it and then apply a high pass filter at the box tuning frequency. That will increase VLF sensitivity considerably and you can back off the power a bit.

These drivers should barely move before they start busting stuff up in your house. If you're getting anywhere near xMech then you might have a serious node problem in your room. Load the boxes up in some corners and see if that makes the problem go away.

I use a 200 WPC Citation 22 that is capable of dumping 120 amps of current when needed and there isn't any problem driving these monsters to unbearable levels. My room is fairly small though.
The box is right about 5cf net with 2 drivers in it and it was clearly too large when I put that one driver in it and sealed the other hole on Friday.:o: I need to get around to actually measuring that but BBP6 puts my qtc at .609 with 2 15's. I guess I want to strive for .707 as I've been reading and my box is still to large for 2 15's. I've been wanting to build new single speaker subs anyway.

So it looks like this last failure was my fault, again.:o:

[grumpy]

IIRC, the Revel sub using the sub1500 was less than
2ft3. EQ/contouring, room gain, placement and huge
dedicated amp did the rest.

[pos]

Maybe you should look for W15GTI / 2256G.
These cannot be broken with excessive excursion (braking coil), and can accept huge amounts of power (800W continuous). ULF is only about moving air without too much distortion, and these drivers are very capable.

[4313B]

Maybe you should look for W15GTIYeah, it's a higher Q design that's made to dump serious amounts of VLF in smallish boxes. It's used by people who like to beat the unholy crap out of their drivers and it actually likes the abuse. Look at the recommended JBL box designs for it.

[pos]

The recommended enclosures are for in-car use (room gain starting high in frequency), but for home use a 9 cu ft enclosure tuned to 20Hz gives great results. In such a box it is more efficient than a 2245H in the VLF (and also takes a *lot* more power and excursion abuse without increased distortion or power compression). But of course above ~40Hz the 2245H has the edge.

[4313B]

Yeah, I can't remember what the group delay is for a box that large. Some people don't care about such things. Some people say you can't hear it and yet some people still insist on sealed box systems because they "sound better" due to minimal group delay and maximum transient response. Who knows... I guess I don't really care. I already have what I like. :p


That Qtc of 0.609, if it is real, shouldn't be too bad.

[maxwedge]

Yeah, I can't remember what the group delay is for a box that large. Some people don't care about such things. Some people say you can't hear it and yet some people still insist on sealed box systems because they "sound better" due to minimal group delay and maximum transient response. Who knows... I guess I don't really care. I already have what I like. :p


That Qtc of 0.609, if it is real, shouldn't be too bad.
I'm going to try and measure the qtc Sunday and I don't know if I can hear group delay or not but the sealed sub sounds real clean.

[maxwedge]

Maybe you should look for W15GTI / 2256G.
These cannot be broken with excessive excursion (braking coil), and can accept huge amounts of power (800W continuous). ULF is only about moving air without too much distortion, and these drivers are very capable.
I've looked for those from time to time with not much luck.
Plus I'm not much interested in picking up a couple of vt4881 cabs to get some.


Yeah, it's a higher Q design that's made to dump serious amounts of VLF in smallish boxes. It's used by people who like to beat the unholy crap out of their drivers and it actually likes the abuse. Look at the recommended JBL box designs for it.
Believe it or not I'm not into destroying my drivers, I just get brain dead from time to time.:banghead::confused:

[4313B]

Believe it or not I'm not into destroying my drivers, I just get brain dead from time to time.:banghead::confused:Obviously some of these drivers had manufacturing issues. It's too bad really. The good ones are quite impressive. So much so that JBL and Revel continue to use the next generation versions. Arguably something like the W15GTi should be considered a "last resort" solution.

[grumpy]

Re: W15GTI/2256G ... I expected to get some feedback regarding that suggestion :)

background:
I'm using two 2242/4645 cabs in the "HT" area, and that's unlikely to change soon.
I built up a pair of SUB1500 ported cabs and ran them in the 2-ch music-only area.
Both can be quite compelling, and I've yet to blow up a driver. If I were to reuse
the SUB1500's in another configuration or for HT, I think I'd try sealed, ~2-3ft3.

The 2256G nearly fell into my lap (price-wise, less than the parts-express SUB1500
blowout, and -much- less than a recone of either) and it seemed a likely candidate
to make an entertaining bass-shaker type sub, and fairly destruction proof.
Given Maxwedge's experiences and usage, it seemed worth bringing up as an option.

Note:
Anyone considering this -should- be thinking seriously about where a used W15GTi
might have lived in it's previous life... SPL contests and concert array systems can
be pretty hard on a driver.

So..., I don't expect a W15GTi/2256G will make the be-all end-all subwoofer,
just one that is fun, inexpensive (relatively), not too huge, and a bit forgiving of abuse.

[demanddeepbass]

Just spotted this thread and thought I may be able to add some value.
I've got six of these and have experienced both modes of failure (spider - basket and spider - cone). I'm sure the spider - basket was a manufacturing problem as has been well documented here. It came away so cleanly the glue had obviously not adhered properly.
I'm also sure that the spider - cone failure was caused by abuse / over exertion. I accidentally played an 800w 10Hz track off a CD through it and heard the coil former hit the backplate before it failed. My boxes were ~2.8cu foot but still early in the build and they had leaks. If you are running a well sealed box you should be able to push the cone in by hand and then see it return - SLOWLY - to the rest position. The extra back pressure will help prevent over excursion. If you are running ported you must filter below the tuning frequency.
I sealed up all the internal joins with a bead of silicone, also did the backplates, handles and connectors. The seal is much better now.
I fixed both the problems I had with mine using epoxy - a big thick bead of it at the cone join and a thin layer at the spider. No problems since then and they have been used hard with 800w from Crown K2s.

[maxwedge]

Just want to say thanks to Edgewound of Upland Loudspeaker Service for rescuing my SUB1500 that I blew the spider off of the basket, incredible work. :)
And I'm glad I didn't try to fix this one myself!:D

So, I'm now working with 2 SUB1500's and life is good again.:dont-know:
Still using the same 2-15 box but separated the chambers and reduced the volume to about 1.5 cf each.

And, it looks like kits are not available anymore.:crying:

[baldrick]

I have some unused sub1500, is there anything I should do to prevent the from failing before I start useing them?

Is aprox 3ft sealed the preferd box or are there any better alternatives?

[mrbluster]

It's been a while since I visited this thread. NO, there is really nothing for you to do. An inspection of the spider seal might be a good idea. Take note of the color of the glue. It had been reported here that failure could sometime be predicted by what glue was used and identified by the color. I can't remember the details regarding color but you should be able to find it earlier in this thread .

Three cubic feet sealed will work great. Depending on the room you may not need any EQ. This Driver is unusually versatile and can be used with great success sealed or ported. It is also robust and can except substantial EQ without protest. It is is driver worthy of a great cabinet and your best efforts. You won't be disappointed.