prevent hardening of speaker surrounds

According to the MSDS, the primary solvent contained in Armor All is Propasol P(a glycol ether). I won't bother listing other components. This solvent should be OK for butyl surrounds or epoxy(used in many adhesives - check with your manufacturer). However, it would not be safe for use on vinyl, acrylic, many polyesters(which also are used as adhesives), ethylcellulose, nitrocellulose, certain chloro or fluouropolymers(Saran or Kynar), or polyurethane. Do not use it on foam surrounds unless the foam is a polypropylene type. And make sure of the type of adhesive used to attach your surrounds. Also, keep it off your speaker's finish at all costs. These finishes are usually polyurethane or lacquer(usually nitrocellulose) based, and will be attacked by glycol ethers. Don't ruin that furniture quality finish you paid so much for in the first place.

Trelja; I want to thank you for your responses. Although I am not a chemist, I did get a minor in chemistry in college. I did not like the requirement of German for chem. majors and this was the rebellious 1960's, so of course I quit chem. Although there is no occidation occuring as yet, it is inevitable. The ozone in the atmosphere will see to that - as well as UV (a good reason to keep grills on). When you buy speakers as expensive as Aerial 10ts you want to keep them around for some time and in peak operating condition. It just seemed prudent to see if there was some way of maintaining the operating parameters of the speaker surrounds as long as possible. We audiophiles seem to obsess over things like jitter, green magic markers, pucks etc. that we forget that the suspension of a speaker is probably at least as important. Thaks again. mjdraper@earthlink.net

To clarify something, here, I agree that the suspension of the speaker is of paramount importance. However, it's the rear suspension on cone speakers (the spider, a woven fabric) where the primary burden lies, with respect to how the cone behaves, since it is connected to the "balanced center" of the moving mass of the diaphragm. The front "surround" serves primarily to keep the cone centered during motion, and serves an extremely minute roll in the "suspending" of the diaphragm's mass. Therefore, changes in sonic performance over time are due to changes/wear in the spider, and not so much from the front surround. SUBARU ALLUDES TO THIS ABOVE.

I agree 100%. The part we don't see(suspension) is where is much more critical. I also know that speakers with different surrounds(foam, linen, butyl, etc.) sound different. Neither point was the issue in this thread, however. Appreciate your perspectives Carl, and your compliments Mjdraper. Thanks to both of you!

While i agree with Carl that the spider is "theoretically" the most important and stressed member in the suspension of a dynamic driver, i would like to add some observations. Having several older drivers that were in excellent shape other than foam rot, i took these and had them re-foamed. Everything on the drivers remained the same ( cone, spider, etc..) and the only thing done was to replace the foam surrounds. These drivers required break in for optimum performance, just like brand new drivers. Even though the surrounds are "supposed to" have a minimal effect on their output, the bass response and several other traits were greatly improved once the speakers had been "driven" for a while. This made me re-think my stance on the importance of the surround quite a bit. I am hesitant to use any type of "conditioner" on them at this point in time unless something in the "new and improved" category pops up real soon. Sean >