Help attaching tinsel leads

[mikay786]

Working on this Sunfire HRS-8 subwoofer with a dead woofer driver.

I assumed it was the voice coil as was reading open on the terminals. But after looking at it a bit more closely it could possible be a broken tinsel lead on the negative side.

Struggling to see how i can get to it without causing damage or creating a bigger job.

I removed the dust cap as assumed tinsel leads would start from there but nope looks to start from the side. Making it harder is they seemed to be covered in glue. The glue BTW looks to be also separating from the spider inside where it attaches to the cone?

Any ideas or suggestions? was hoping to get someone / a company to deal with it but cant seem to find anyone in the UK who does this sort of work.

[stj]

Re: Help attaching tinsel leads

look on ebay for "conductive glue" or "wire glue"
i'v not tried it yet - but it looks interesting.

[mikay786]

Re: Help attaching tinsel leads

I've managed to chip away at the glue and expose both winding ends and am now getting a resistance reading.

Both tinsel leads were broken inside the glue, with slight charring at the break. Connected a 9v battery to the exposed leads and speaker thuds. Thats a good sign right?

If replacing tinsel leads can they be left to hang freely or do i need to weave them as they are in the pics above. Also should i also redo the glue i have removed that was covering the solder points from tinsel to windings?

[Khron]

Re: Help attaching tinsel leads

You shouldn't need to weave them through.

I remember a few years ago i bought a pair of Alesis M1mk2's with one dead woofer - turned out that the tinsel lead had broken off the end of the voice-coil wire.

Don't ask me how, but i managed to keyhole-surgery-solder the two back together, and after it cooled down, drenched the joint in superglue / cyanoacrylate, in the attempt to mechanically reinforce it.

I ended up selling that pair to one of two friends, can't remember which. But what i do know for sure is that neither has complained about any problem with them, to this day

[mikay786]

Re: Help attaching tinsel leads

Luckily ive got just short of a cm of exposed voice coil wire to play with. Measured tinsel and is 1.4mm so ordered some of that on eBay along with some gorilla epoxy for the spider and some black silicone adhesive to put the dust cap back on.

Think it may be best to epoxy the solder joint as it original was and leave the tinsel free floating from there which should keep it free from fatigue.

[momaka]

Re: Help attaching tinsel leads

Meh. Tinsel leads are overrated. You could just use regular 20-18 AWG PVC-coated wire and put regular silicone on both ends after soldering it (to prevent fatigue near the ends).

No need for special black silicone for the dust cap either (though it will certainly look better). Depending on the cone material, you may be able to use other types of glues. For paper cones and dust caps, I use wood glue. It dries to a near-transparent finish, so it looks alright. It's also easier to apply and thus not as messy as silicone.

[mikay786]

Re: Help attaching tinsel leads

Glad to say got this up and running, was a pain soldering, only about 6mm to solder to and because its attached to the coil was absorbing the heat. But got a solid joint on it and all glued up can't even tell. Powerful little beast!

[Khron]

Re: Help attaching tinsel leads

A whole 6mm? Pfff... That's easy street, you could do that with your eyes closed

I barely had maaaaybe 2mm of visible wire end on that Alesis woofer... :P But glad to hear you got it sorted

[kndm17]

Re: Help attaching tinsel leads

hi all.

can you also give me the value of resistor in AMP Section. this the Reference R107.

Thanks.