Advent/1 woofer not working

[Guest jcmorrison]

I recently refoamed a pair of Advent/1s and one of the woofers is not working.

When I removed the dust cap of this speaker, one of the strands on one tinsel wire broke, but I pushed it back down and put glue on the break. There is no other problem apparent—the connection wires from the basket to the voice coil are fine, and the tweeter is working. Is there anything else I should be checking for?

JM

[RoyC]

There is no way that woofer will function with a "glued" broken voice coil lead...solder is your only hope.

Roy

[dynaco_dan]

Hi there;

Roy is quite correct.

One suggestion that I might give is, the tinsel will likely be too short now for proper cone travel.

Buy a roll of small guage solder remover lead, $1 - 2.00, it is a finely stranded copper rosin flux enriched tinsel equivalent and use it as a splicer or extension piece.

They come in several guages and the smallest is adequate but allow a little bit more in length to allow for the soldered connections not being flexible.

In normal use there is not a lot of extra tinsel between the soldered terminals and the cone connections.

Do not allow too much in case it should touch the woofers cone or steel frame, though.

You cannot tape or insulate these leads.

Can you possibly download a clear, well lit, photo of the break, so that we might have a boo, please, before you attempt your repair.

[Guest jcmorrison]

Roy and Vern,

Thanks for your replies--solder would clearly be the way to go at this point.

But I may have given the wrong impression about the degree of the break. Of the half-dozen or so tiny strands of the tinsel wire, only one broke. Nothing else was detached from the inner surface of the cone. Would that cause a complete loss of signal in itself?

Jim

[dynaco_dan]

Hi Jim;

I just re-read your intro to this topic again.

I am now looking at your problem differently.

You cut open the dustcap?

The tinsel lead you mention is in the voice coil area looking down into the cone into the dustcap area?

I originally thought that you would only see your, TINSEL BREAK", looking into the lower cone frame area from the side?

If you are referring to looking at a side frame view, then one of many tinsel leads broken will not have any effect on the signal to the woofer, unless the broken lead is touching, shorting, the other tinsel lead.

[Guest jcmorrison]

Vern,

Thanks for following up. I should have been more explicit.

If you look down at the dust cap, there are two sets of tinsel leads emerging from under it and extending a couple of inches, covered with transparent glue, and apparently soldered at their ends to the front surface of the paper cone. Only one of the tiny wires that compose one of the sets of tinsel wires was broken, when I lifted the part of the dust cap covering it.

Yes, I removed as much of the dust caps as possible to get at the voice coil, to put shims in the voice coil gap to keep it centered while gluing the outside edge of the new foam to the basket. This was as directed by the foam kit producer, Newfoam.

I wouldn't think that such a tiny break would cause the signal to fail, so I'm wondering if there might be some else wrong that was there before I started.

All the wire connections underneath the cone (looking at it from the side) look fine.

Jim

[Carlspeak]

>Vern,

>

>Thanks for following up. I should have been more explicit.

>

>If you look down at the dust cap, there are two sets of tinsel

>leads emerging from under it and extending a couple of inches,

>covered with transparent glue, and apparently soldered at

>their ends to the front surface of the paper cone. Only one of

>the tiny wires that compose one of the sets of tinsel wires

>was broken, when I lifted the part of the dust cap covering

>it.

>

>Yes, I removed as much of the dust caps as possible to get at

>the voice coil, to put shims in the voice coil gap to keep it

>centered while gluing the outside edge of the new foam to the

>basket. This was as directed by the foam kit producer,

>Newfoam.

>

>I wouldn't think that such a tiny break would cause the signal

>to fail, so I'm wondering if there might be some else wrong

>that was there before I started.

>

>All the wire connections underneath the cone (looking at it

>from the side) look fine.

>

>Jim

>

>

You may have a shorted VC. Check it with a VOM. You must get a reading of something in the 3-8 ohms range to confirm it is okay. That may be your problem instead of one, loose part of a tensile wire.

It's all about the music

Carl

Carl's Custom Loudspeakers

[RoyC]

Jim,

Assuming the woofer worked before you removed the dust cap, it is possible that the very fine voice coil wire underneath was broken or cut upon removal of the cap. The signal is most likely not reaching the tinsel lead on the cone at all.

Roy

[Guest jcmorrison]

Carl and Roy,

Thanks, I'll check out these possibilities.

Carl, since I'm not practiced in the art of bench work, what is a VOM? And where would I place the probes to check the resistance?

Jim

[Carlspeak]

>Carl and Roy,

>

>Thanks, I'll check out these possibilities.

>

>Carl, since I'm not practiced in the art of bench work, what

>is a VOM? And where would I place the probes to check the

>resistance?

>

>Jim

VOM stands for Volt Ohm Meter. You can borrow one or purchse an inexpensive one from Sears.

attach the leads to the two terminals the speaker wires connect to. Be sure to disconnect the speaker wires first. Set the VOM to "OHMS" and see what you get! You should get a reading in the 3-8 ohm range. If nothing happens, there is a short between the connectors and VC. You can also touch the tinsile wire with the probes to see if you get a reading. If you don't the voice coil is a dead duck and another recone job will be needed.

It's all about the music

Carl

Carl's Custom Loudspeakers