RTA 15TL - speaker cones "tacky" to the touch.

AntiGravityHero

Hello...

I was recently given a pair of RTA 15TL speakers. They're obviously not the newest of the Polk Audio line, but they look and sound fantastic.

I recently removed the cloth grilles and have noticed that the speaker cones are all "tacky" to the touch, much like paint that's not quite dry. The speakers seem to perform just fine, though.

Is this normal for these speakers, or a sign of age or impending failure or other issues?

Thanks for any insight.

-Samuel Livingston

ken brydson

Armor All??

Been some discussions recently regarding pros/cons of using AAll on drivers. Stickyness was one con that was mentioned

RuSsMaN

Quit touching them first of all.

The are Poly-propylene coated, paper cones. The only thing not-tacky about them is their sound.

Cheers,
Rooster

F1nut

AntiGravityHero,

Welcome to the forum.

Sticky cones, huh? Well, that isn't good and is a sign of impending failure. I'll do you a favor and take them off your hands, I could use the cabinets.



















Ok, seriously........they are fine and are suppose to be sticky, so don't try to clean them or do anything stupid like put Armor-All on them. Sit back, relax and enjoy, just leave the grills on, so you won't have to worry about dust getting on the cones. If you have any other questions about them, just ask. If you ever do want to sell them, please let me know.

F1

AntiGravityHero

I've never used Armor-All on these, nor would I even THINK about it, unless I heard otherwise directly from a Polk engineer. They're supposedly-high(er)-end speakers, not a friggin aged dashboard (this is my opinion)

That's good to hear that this is "normal". I guess I'm not used to speakers of this caliber. They really do knock my socks off, and I wouldn't let them go unless I needed the money badly

Thanks for everyone's advice. Much faster response than I anticipated.

dthomps

yeah, I have heard good things about your speakers, never listened to them, but many people here love them.
I have several pair of Polk's from around the same period and the mid drivers are all tacky too.
What kind of equipment are you using with them?
Take care.
Mike

jtconnell

The whole speaker cleaning issue has been a popular topic of late. I'm still not sure about Armor All. Some seam to swear by it and others swear not to use it with equal passion. You can read more with the following posts:

http://clubpolk.polkaudio.com/forum/showthread.php?s=&threadid=10132
http://clubpolk.polkaudio.com/forum/showthread.php?s=&threadid=9824

With respect to the "sticky stuff", the following was the response from Polk:

The following was the response I received from Ken who had forwarded my inquiry to Stu regarding cleaning the speakers.

""Hello Jason,

The following is a reply from Stu Lumsden, the head of engineering:


"The top treatment on the cone is a nitrocellulose lacquer. It coats only the cone. The dust-cap is permeable - it passes some air. I don't suggest cleaning the cone. The collected dust on the cone will not cause a sonic problem. If there is a white residue on them then it maybe "out-gassing" from the cyanoacrylate [CA] glue used to assemble the driver. This can distribute a white participate during curing and can be cleaned off with a brush. You can use a damp cloth or a cloth with some acetone but don't get it on the cone."
Regards, Ken""

I'm not sure what the laquer is for on what effect Armor All or other cleaners wil have on it. My thought is that that's what grill covers are for and leave well enough alone! The acetone comment caused even more debate. I'm moving soon, so I don't have time to really get in there and get my speakers cleaned. After the move (about 45 days), I'll get them spruced up meaning I'm probably one of those people who can't leave well enough alone!

Best Wishes with your Polks!

Jason