BAS Message
November 2019

1.  V41N1 of the BAS Speaker has been published. It features 2 meeting summaries: the April 2019 Recording Panel by David Hadaway, the Beolab 90 Loudspeaker by John S. Allen; and CES reports by Kenneth Wacks.

2.  Replacing Speaker Surrounds

I’ve owned a pair of Acoustic Research AR-9s for many years. About 10 years ago the woofer surrounds for one speaker rotted out. I had heard of do-it-yourself repair, but decided to buy two new woofers. I installed them and discarded the old drivers.

Recently one of the woofers in the other speaker rotted. I decided to try a kit from You get surrounds for two speakers, glue and instructions. The instructions were good, but I watched the recommended video on You Tube just for reassurance. The first step is completely removing the old surround. It is in pieces and you have to scrape it off the cone, then off the frame. If it is stubborn you can use alcohol to soften it. You then apply a bead of the glue on the edge of the cone and spread it smoothly around with your finger, then position the surround and start pressing the two together, working your way around. At first the halves don’t adhere — it is a slow setting adhesive — but eventually they stick together. You need to lift the cone to get room for your fingers to press the halves together. After an hour of curing you do the same for the surround attachment to the frame. Before you glue you want to exercise the cone to make sure it is centered and not rubbing. You can skew it a little by the position of the surround on the frame. You are mainly relying on the spider to center the cone—that is usually OK. In advanced repair the dust cap is removed and shims are used to center the cone. Usually that is not necessary.

At one point I had spilled some glue on the surround so I used some alcohol to easily remove it. Then the surround started puckering from the alcohol! I thought I had damaged the surround. Fortunately after it evaporated the surround returned to normal.

After installing the woofer everything was fine. Then a month later, rattling sounds again—the other woofer had rotted. So I used the 2nd surround kit and all was good. As a test I played the Saint-Saëns from the BAS Test CD 1 at high volume and there were no signs of any distress.

I wish I’d saved the first 2 woofers.

email me here

Webmaster's Note: The two great recone and parts companies are both right near each other: is in St. Pete and The Speaker Exchange is in Tampa. The third, a bit smaller but still fascinating, is , in Tucson, Az.  — Barry


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PO BOX 260211
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updated 11/15/19