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View Full Version : Woofer surrounds, specifically 14h-1



opimax
12-06-2006, 03:36 PM
Todays 2nd question/comment is about my woofers in my 250tis.
I don't find these speaker particularly bassy as their reputation. the 120ti I have mave even seem like may even produce more. I realize the most usual suspect would be the room and I am not disagreeing but since I took 1 the 250 apart (to install Guido chage coupled XO whose appearence in craftmanship is like beautful art work :applaud: ) I gently, very gently, probed and such the surrounds.

I thought they felt stff, stiffer than the new ones in the 128h1, or even the older one we didn't do. Unfortuneately I don't have the experience to know if this is too stiff. But this would cause a problem if it is too stiff.

How does the home user know? I just want to be sure

I don't mind refoaming if needed or even just to make sure all ok. My concern would be making an expensive mistake and actually damage them, not "wasting my time" as to me they are more than worth it!!

If the only choice is bring them to a professional I just want to make sure he is at least 1/2 as passionate as I am about my toys. I certainly would trust the pros here but none in the DC area that I know and given a choice of course local is much preferred, especially this time of year and past history w/all the shippers is not perfect

Mark

Guido
12-07-2006, 03:53 AM
The surrounds should be smooth. Bring them to a specialist for refoaming.
I hope that some of the forum members can recommend one reliable shop near you.

If not, ask subwoof.

GordonW
12-08-2006, 07:47 AM
At one point, the supply of aftermarket LE14A/LE14H/LE14H-1 surrounds was plagued with pieces that were overly stiff. It's gotten better now... if they're out of spec, they're likely to be LESS out of spec, and more of them will be in spec, than previously.

Could be that the LE14H-1s in those 250Ti's were previously refoamed with some of the overly-stiff stuff... if so, then a repeat refoam may solve the problem.

Regards,
Gordon.

grumpy
12-08-2006, 07:54 AM
FWIW:

$150 gets you a way to test 'em yourself

http://www.woofertester.com/products.htm

or perhaps someone nearby has facilities (such as WT2 or less novel means) that could
check them for you, for fun or profit...

(no relation/connection to vendor)

opimax
12-08-2006, 08:16 AM
Gordon, they were definetly refoamed before. I was told that when purchased. I was thinking either the samething or it was done much longer ago then I thought. Are these particularly harder than others? I read the Auaplas made it more difficult but we did the 128h-1 (120ti) successfully.

Grumpy , looked at the link, forwarded it to my friend, if he will split it w/me I think it may happen , thanks

GordonW
12-09-2006, 06:30 AM
Gordon, they were definetly refoamed before. I was told that when purchased. I was thinking either the samething or it was done much longer ago then I thought. Are these particularly harder than others? I read the Auaplas made it more difficult but we did the 128h-1 (120ti) successfully.

Grumpy , looked at the link, forwarded it to my friend, if he will split it w/me I think it may happen , thanks

They are some of the more difficult refoams. The combination of tight voice coil clearance with the limited "wiggle room" given the very narrow lip around the edge of the driver frame, makes them a real trick to get right sometimes. Sometimes (if the original cone kit was mounted in the frame DEAD ON STRAIGHT) they'll be easy, but sometimes, it'll seem like it's never going to line up right. I've had to cut dustcaps and shim these, several times, to get the things on in proper alignment.

Also, the other caveat about aftermarket surrounds on these- SOME of them DO NOT FIT RIGHT into the frame recess. I stilll have some, that have that problem. If so, it's possible, if you're really obsessed and stubborn, to trim them down to a proper fit in the frame... but it's a real PITA to do.

Fortunately, more of the ones available now, fit better.

HOWEVER... if you get one that doesn't want to fit the CONE right, stop, and send them back immediately. I have seen a very few, in the past, that were simply too big in all dimensions... like a 1/8" or 1/4" too big in each diameter. THOSE REALLY SUCK...

I've gotten where I don't like to mail out these type surrounds to people, due to the tolerance issues... many times, I can get them to work right if I have the woofer in front of me... but I don't want to saddle other people with that sort of a difficult job, unless they're VERY AWARE of what they're getting into...

Regards,
Gordon.

DavidF
12-09-2006, 11:25 AM
Todays 2nd question/comment is about my woofers in my 250tis.
I don't find these speaker particularly bassy as their reputation. the 120ti I have mave even seem like may even produce more. I realize the most usual suspect would be the room and I am not disagreeing but since I took 1 the 250 apart (to install Guido chage coupled XO whose appearence in craftmanship is like beautful art work :applaud: ) I gently, very gently, probed and such the surrounds.

I thought they felt stff, stiffer than the new ones in the 128h1, or even the older one we didn't do. Unfortuneately I don't have the experience to know if this is too stiff. But this would cause a problem if it is too stiff.

How does the home user know? I just want to be sure

I don't mind refoaming if needed or even just to make sure all ok. My concern would be making an expensive mistake and actually damage them, not "wasting my time" as to me they are more than worth it!!

If the only choice is bring them to a professional I just want to make sure he is at least 1/2 as passionate as I am about my toys. I certainly would trust the pros here but none in the DC area that I know and given a choice of course local is much preferred, especially this time of year and past history w/all the shippers is not perfect

Mark

Mark, I think it is difficult to compare the relative stiffness of the LE14H-1 surround with the 128H. The size differential can give you the impression, I suppose by feel, that the larger 128H surrounds are more flexible, compliant, etc. My experience with the 128H-1 (and 128H) in volumes of 1.75 to 2.5 cu ft is that they will seem (and are) bass heavy when influenced by boundaries. The effect, though, was not to my personal liking. The perceived increase in bass quantity was not realistic. Too much overhang on bass blurs the true bass content. You may want to consider where the systems are placed and that boundary influence on bass response when trying to assess the bass quality v. quantity.

David F

opimax
12-10-2006, 08:06 AM
thanks both for your responses.

yesterday my friend and i went feeling surrounds on all my speakers. aside from being hard to get to a few it was decided that the 14-1 were the stifffest in the house and by far the stifffest jbl. the final speaker was a 2245. we shall attempt to refoam. my friend is the aggressive one, we can do this, lol. the 128h1 came w/a 30hz tone to center the cone, worked very well

i will show him gordans response before we begin though. we get our foam from the this site's recommended place , can't remember the name , he always ordders them. hopefully we will get some good ones, but will be checking closely.

david, while it is a boomier, blooming bass in comparison the difference is not subtle at all.

when done the 250ti pair will have newly foamed 14s, replaced 104h , aquaplas tweeters, and charge coupled xo.

i need 2 108h for my center project, available new. i could put those in the 250 and use theirs for the center project, damn near brand new speakers :applaud:

how does a consumer order new drivers. i looked at jblproservice site, didn't see the 108h listed while on another thread they were stated as available...

mark
hope to finish beffore new years eve

Zilch
12-10-2006, 11:43 AM
how does a consumer order new drivers. i looked at jblproservice site, didn't see the 108h listed while on another thread they were stated as available...For parts unique to consumer products, you find the part number from the tech sheet or repair parts listings and order from Harman Consumer Parts.

opimax
12-10-2006, 03:58 PM
a quick report. installed xo, reinstalled 14 and 108 , installed new 104, atempted to install an aluminum 44 untill mine come back. didi't work as it is threaded and the 44ti is not. i will not put the tweeter over back on and let the aluminum tweeter sit there connected while breaking in.

i believe it takes 2 weeks to break in. i am going to plug in the battery in put on fm tuner static at low level ad let it play while i am not home

all that sound ok. i was orginally going to do 1 then the other but time and changng multiple varibles at one time make most comparisims pointless

mark