I have 2 pair of these 781's and a center channel that I haven't used in some time. I just went to fire them back up and the woofers are all bad. Upon inspection I noticed the lead wire to the coil is badly corroded. I heard that the ferofluid could cause this to happen. Now I cannot find the exact replacement and I'm not sure how to buy a driver for this cabinet. I just wonder if I should fix or scrap? The cabinets are really nice and the tweeters are fine. They are bi-wired.
Hi, are you saying that copper braid wires that go from driver terminal to the voice coil are damaged? Can you bypass these with a piece of another wire to see if it makes a difference?
There's no ferrofluid applied to a midbass. That is a tweeter thing, and FWIW, new tweeter ferrofluid is easy enough to buy. The oil evaporates and solidifies over 10-20 years and stops the tweeters working.
It's not easy to fix tinsel leads on a midbass. I would fancy the Peerless by Tymphany 830874 6-1/2" PPB Cone HDS Woofer Peerless 830874 polycone if it fits. It shouldn't be hard to adjust the tweeter level if necessary. You usually just adjust a wirewound resistor. These resistors cost less than a buck.
These look like goodish 6" two way speakers. I'd definitely fix them.
It's not easy to fix tinsel leads on a midbass. I would fancy the Peerless by Tymphany 830874 6-1/2" PPB Cone HDS Woofer Peerless 830874 polycone if it fits. It shouldn't be hard to adjust the tweeter level if necessary. You usually just adjust a wirewound resistor. These resistors cost less than a buck.
These look like goodish 6" two way speakers. I'd definitely fix them.
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Thanks. The lead wire is corroded right at the winding very difficult to get to. I had a BIC DV62CLR-S sitting around. The drivers in it fit perfectly in the cabinet. The tweeters are still working well. Should I attempt to add the ferrofluid?
I have the center and surround from this series and every driver shows the same corrosion and are non functioning. The tweeters all still tweet.
I replaced them with the drivers from an unused Bic DV62CLR-S. I'm not sure if it's the best pick buy they fit.
I took a driver out of a Bic DV62CLR-S and it fit pretty well. I'm not sure if this is the answer.
I have the center and surround Missions and all the mid bass have the same issues. All the tweeters still tweet. Maybe I should look up the ferro refresh.
It's hard to know what is going on with your old speakers.
At a complete guess, I'd think you are looking for new 6" polycone aka plastic woofers: ScanSpeak Classic P17WJ00 6.5" Woofer
Ferrofluid is a rather inexact science which only applies to tweeters. Ferrofluid 100uL General Purpose for 1" Diameter V.C.
The idea is the oil wicks away the excess heat from the 5W tweeter. Maybe it helps. Maybe it doesn't. The bottom-line is ferrofluid tweeters last longer than the more naked type.
At a complete guess, I'd think you are looking for new 6" polycone aka plastic woofers: ScanSpeak Classic P17WJ00 6.5" Woofer
Ferrofluid is a rather inexact science which only applies to tweeters. Ferrofluid 100uL General Purpose for 1" Diameter V.C.
The idea is the oil wicks away the excess heat from the 5W tweeter. Maybe it helps. Maybe it doesn't. The bottom-line is ferrofluid tweeters last longer than the more naked type.
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