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View Full Version : Polyether or butyl refoam/resurround?



more10
09-15-2018, 12:16 PM
This is my first resurround work. Do I need to remove the dustcap in order to shim the voicecoil?

Speaker exchange has this resurround kit for my 117H: https://reconingspeakers.com/product/8-jbl116-refoam-kit-rfk8-jbl-116/


*New polyether foam surrounds last longer than the originals*

Maybe true but it will not look as good as black butyl.



I also need to choose dust cap. The one matching is 2.875", screen. It this the one I need?

Any advice appreciated.

Mårten

Odd
09-15-2018, 03:05 PM
You buy Speaker Foam Surround Kit from Rick Cobb (looneytune2001) on ebay
Replacement of dust cap is not necessary.
There are many recommendations of his kit on the forum.

RMC
09-16-2018, 04:39 PM
Hi Marten,

Though people here who have done many say they don't need to remove the dustcaps anymore in order to shim (some using 30 hz test tone), when refoaming my 2214H I did cut them, without removing the caps (no cut near the wires) since I also had to remove rotten foam inside the driver and wanted to save the original dustcaps... I used a scalpel like surgeons use to make a nice cut just above the black glue line. These things cut unbelieveably and are available in different sizes and shapes.

There's an old timer refoaming fellow from Texas who claims having done many hundreds of these and he swears you do need to shim therefore cutting the dustcaps... So two schools of thought here. If you want the link to that Texas fellow video let me know, i think i still have it in my laptop.

I tend to think like you that for appearance it may look better with rubber surrounds... I've seen driver pictures with foams and they lack surround "punch".

BTW I see that midwestspeakerrepair.com/shop/speaker-repair-kits/jbl 117H..... has a complete rubber surround kit for $30. : surrounds, instructions, shims, dustcaps, glue, plus a note of caution if not using shims... If you can save the original dustcaps the better, minimizing adding more cone mass while keeping some of the original driver look as I did. All the relevant dimensions are given on that web page so you decide if this fits exactly your needs.

I make no representation about that seller, good or bad, i'm not associated with them nor have bought anything from them. Regards,

Richard

EDIT: There is a thread or post from Barry (1audiohack) about his use of butyl rubber surrounds on larger JBL drivers, and if my memory is correct he was delighted by the result.

more10
09-17-2018, 11:51 AM
Thanks for advice! There are no butyl surrounds, so I will go for the foams. Also after talking to my friend Blomman I decided to shim the voicecoil. So a complete kit from Speaker Exchange it is.