I have a 91 300E that has the stock Becker with the door mounted subs, two woofers and 4 tweeters on the rear parcel shelf, and of course the really odd sized dash speakers.

The paper cones on my speakers were degraded (13 years will do that) and sounded like they had sand in them. I didn't want to spend the $$ for the Rainbows for the front, and who knows how much for the rear shelf.

Here is what I did: I spent $100 on two pairs of Pioneer speakers, one 4" and one 5.25". I have had several Pioneer speakers over the years in several different cars and my boat and they have always satisfied me as a very good, solid performer.

I then removed the stock speakers, front and rear. (I haven't worked up the courage to take off the door panels yet to investigate those.) BTW, the speakers DID have sand in them

I took the stock speakers and carefully cut out the speaker cones and voice coils. After about 1 hour of carefull Dremel work I had some pretty decent mounting brackets for my new speakers. I was able to carefully preserve the stock speaker wiring and soldier pigtails from the new speaker terminals to the stock speaker wiring. On the rear speakers, this allowed me to keep the stock tweeters

I used a strong non-hardening adhesive to glue and seal the new speakers on the stock brackets. The speakers went back in after the glue dried with no problem at all.

The stock stereo now sounds much, much better. The advantage of this is that I did not alter either the car or the wiring of the stereo and it still looks totally stock. The disadvantage is that I now have slightly smaller speakers installed. But if one wanted to, then could do this with much higher end speakers, like Infinity Kappa or JBL or whatever. I still could, it would be extremely easy for me to cut the adhesive and de-solder the wires and then drop in different speakers. But like I said, the Pioneers have been very solid performers for me and currently sound great.

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