LE 14A surround

[johnaec]

Wasn't the original white lansalloy surround on the original LE14A's mounted on the front of the cone anyway? In this case, I feel it totally acceptable, and possibly preferred, to put the new surrounds back in the original position on the front of the cones, even though the foam is now black. I even have 2 sitting here right now that were done that way, and though the color of the foam is different,specs should be closer than if mounted on the back sides. Am I missing something here?

John

[speakerdave]

. . . . Am I missing something here?

John

I think Rick Cobb told us no one was making a foam now for front mounting, only for the back. Putting the available foam on the back would create some small amount of forward pressure against the spider. I've had sleepless nights, but not about this.

[brutal]

The only thing I ever had the opportunity to speak to Rick about on the LE14A was the availability or use of a concave surround similar to the original Lansaloy. He advised his surround was intended for convex use facing out and applied to the front of the cone, and that their wasn't a large enough gap between the cone edge and basket to use the foam in a concave manner.

If a large amount of Aquaplas was pulled off then either too much, or too little, MEK was used and the removal process was too aggressive, or the Aquaplas to cone paper bond was already compromised. I was a slow and careful, applying MEK lightly with a Q-Tip, dampening the foam just enough to allow it to peel, and if it resisted too much, re-dampening it - but not to a point of saturation. I wouldn't have felt comfortable doing it without already having a good feel for how much MEK to use based on previous refoam jobs.

[speakerdave]

. . . . If a large amount of Aquaplas was pulled off then either too much, or too little, MEK was used and the removal process was too aggressive, or the Aquaplas to cone paper bond was already compromised. I was a slow and careful, applying MEK lightly with a Q-Tip, dampening the foam just enough to allow it to peel, and if it resisted too much, re-dampening it - but not to a point of saturation. I wouldn't have felt comfortable doing it without already having a good feel for how much MEK to use based on previous refoam jobs.

What he said. The judicious amount of MEK leaves most of the aquaplas, loosens the glue and leaves the lansalloy strong enough to be pulled off in strips, sometimes using a little encouragement with a rounded exacto blade to assist the parting. I practiced on an LE10 that had other problems.

[shaansloan]

If a large amount of Aquaplas was pulled off then either too much, or too little, MEK was used and the removal process was too aggressive, or the Aquaplas to cone paper bond was already compromised. I was a slow and careful, applying MEK lightly with a Q-Tip, dampening the foam just enough to allow it to peel, and if it resisted too much, re-dampening it - but not to a point of saturation. I wouldn't have felt comfortable doing it without already having a good feel for how much MEK to use based on previous refoam jobs.

Brutal I think you definately got it right here....too much MEK.....however it seemed with this pair the Lansaloy was almost permanently bonded to the Aquaplas and was extremely dry and brittle and breaking apart.....I tried to be as meticulous with this as I could.......I am sure I was over agressive with it.....but I wonder if there are some cases when it is just too brittle to remove without damaging the Aquaplas.....

I wont lose much sleep over this one either.......I think I will put TFOF and move on as long as much spider position is not too compromised....... these drivers go in Barsilay cabinets and the grill are not removeable so they cant really be seen anyway....

Thanks for the help.....

Shaan

[herki the cat]

Not a good idea. The cone is rather heavy and gravity won't do it any favors. Best in a verticle orientation.

Well, not mounted in a verticle orientation continues over a long time to completely stretch the spider further out permanantly. I have seen four of each new-in-the-box ... Altec 515-B & JBL 2245 (?)18 inch speakers long-forgotten in storage, face -up in a dealer's back room, where the spiders had streched out a good 1/2 inch permanently. I got them for $100 each. I kept them face-down for many months until the spiders reformed perfectly flat. I am not sure it is safe to use MEK to soften the JBL phenolic spider; for one thing, there is a foam plug in the motor pole piece which reverts to gooy polyurethane eventualy & will creep in the voice coil gap. Gravity did play its part gently. New foam was required on the JBL's, and MEK did help on the Altec "gooped" surrounds.

cheers herki the cat

[bldozier]

here are mine, one LE14 is much older then the other as seen from the pictorial, hopefully the surround will cover the lifted areas.