Peerless corrosion??
Options
JayMX
Posts: 435
So I picked up a pair of really clean Monitor 4’s today for a song. They were missing one MW6500 but I had some spare 6502’s that I loaded in them for testing. They sound great, but while cleaning them up I popped the drivers and I find this white stuff on the backs of the tweeters. It’s all over the magnets and backplanes. It was actually coming out around the screw holes as well. Flakes off when scrubbed, doesn’t burn the flesh like battery acid... 
It doesn’t show up anywhere else in the cabinets. Thoughts? What is it?
It doesn’t show up anywhere else in the cabinets. Thoughts? What is it?Current Collection: Monitor 4a (Peerless), Monitor 5B (Peerless), Modified Monitor 7b (Peerless), RTA15TL (SL3000), SDA CRS+ (194’s), SDA SRS 2.3TL, R100's, R200’s, R300 🤩
Comments
-
Mortite gone bad.Political Correctness'.........defined
"A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."
President of Club Polk -
These have regular gasket material like I’ve seen in other cabinets. Isn’t Moretite usually found squished between the drivers and the MDF? Was it employed in conjunction with the closed cell foam gaskets? This stuff reminds me of battery acid corrosion, minus the burn. Or maybe salt, I didn’t dare taste it though...Mortite gone bad.
Current Collection: Monitor 4a (Peerless), Monitor 5B (Peerless), Modified Monitor 7b (Peerless), RTA15TL (SL3000), SDA CRS+ (194’s), SDA SRS 2.3TL, R100's, R200’s, R300 🤩 -
SnO2Don't take experimental gene therapies from known eugenicists.
-
These have regular gasket material like I’ve seen in other cabinets. Isn’t Moretite usually found squished between the drivers and the MDF? Was it employed in conjunction with the closed cell foam gaskets? This stuff reminds me of battery acid corrosion, minus the burn. Or maybe salt, I didn’t dare taste it though...Mortite gone bad.
Just a guess. I've seen that multiple times, really not sure what it is.Political Correctness'.........defined
"A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."
President of Club Polk -
Political Correctness'.........defined
"A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."
President of Club Polk -
I have a Kenwood woofer that has the same thing, but not nearly as bad. I believe it to be oxidation of some kind, but I really do not know.
-
Looks like it's beenin a very damp location for quite a while.
Baltimore (or New England) basement?
-
They're 4s and are ported, so good gaskets or no, moisture will get in. the front's should clean up nicely. A prescription bottle cap will cover the silk dome perfectly, allowing you to clean off the corrosion, lightly sand and then hit them with some Krylon. For the rear, a soft brass parts brush and some clear lacquer perhaps.Home Theater/2 Channel:
Front: SDA-2ATL forum.polkaudio.com/discussion/143984/my-2as-finally-finished-almost/p1
Center: Custom Built forum.polkaudio.com/discussion/150760/my-center-channel-project/p1
Surrounds & Rears: Custom Built forum.polkaudio.com/discussion/151647/my-surround-project/p1
Sonicaps, Mills, RDO-194s-198s, Dynamat, Hurricane Nuts, Blackhole5
Pioneer Elite VSX-72TXV, Carver PM-600, SVS PB2-Plus Subwoofer
dhsspeakerservice.com/
