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Need help with a Scientific Fidelity woofer

babblefish

babblefish

Active Member
I have a pair of Scientific Fidelity 6.5" woofers (C640-4D) that I bought off someone. These have dual 4 ohm voice coils. I believe these came out of a Scientific Fidelity Tesla speaker. I built cabinets for them and really like their sound. I wired the voice coils in series to get 8 ohms. I noticed that one of them didn't sound quite right and upon inspection found out that one of the voice coils wasn't working. Upon further inspection, it turns out that while the voice coil itself is good, the connection between one of the tinsel wires and the voice coil had broken. There's not enough of the voice coil wire exposed to resolder the connection so I'm in need of someone to repair it, if possible. Otherwise, I'm in the market for a replacement woofer of the same model. Can anyone help me?
 
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Ok, so no one knows anyone that can fix these. So does anyone know if Scientific Fidelity is still around or the manufacturer of their raw speakers? Most of the speaker repair places that I've checked out only replace surrounds or cones.
 
You should post some pictures of the woofers so they can be identified, and close ups of the voice coil/tinsel.
 
So here are some pictures of the speaker. I noticed that the voice coil is not fully disconnected because the ohm meter never shows open circuit, but drifts around from 4 ohms to several hundred ohms depending on how I wiggle the tensel lead. And yes, I checked for a good solder connection between the lead and the terminal. Btw, in the picture showing the leads, it's the bottom one that is flaky.
 

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Sounds like a fatigued solder joint. Someone who is good with a soldering iron can easily fix it. Care has to be taken that solder does not flow up the tinsel like a wick, stiffening it.
 
terpodion said:
Sounds like a fatigued solder joint. Someone who is good with a soldering iron can easily fix it. Care has to be taken that solder does not flow up the tinsel like a wick, stiffening it.
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Possibly, but unfortunately, the solder joint between the voice coil wire and the tinsel is covered with some type of black coating that is hard. Not sure what I could use to remove it without damage.
 
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