audio crossover repair and speaker spares

[ericd]

I've blown the x-overs and the tweeters on my beloved rtl3's , anybody got/had experience sourcing parts for obselete tdl or other speakers, I've done the usual of trawling the bay etc but so far no luck, also any recommendations for repairing the x-overs ?


Tweeter spec : 19mm bi-wired ferro fluid cooled (I think)
X-Over spec : 2 way SON @3Khz

[newsh]

Tweeters actually OC? What are they, soft domes?
Whats blown in the crossovers, the inductors? can you read the values?

[ericd]

Tweeters actually OC? What are they, soft domes?
Whats blown in the crossovers, the inductors? can you read the values?

John,
yip soft domes Vifa D20TD-05-06 or something like it , as far as the crossovers go they look pretty flimsy on first examination (had them for 12 years), caps look really small/puny , apparently the way forward maybe by adding rp1/2 (lpar) resistors to the original tweeter circuit

tdlxover.gif

[newsh]

So are the tweeters blown? Open circuit voice coils? Can you take a pic of the tweet and it's diaphragm? Crossovers components are easy if you have that diagram. If the inductors are melted we have some we could wind down or up to that value. need to get an idea of what the parts look like though..

[ericd]

So are the tweeters blown? Open circuit voice coils? Can you take a pic of the tweet and it's diaphragm? Crossovers components are easy if you have that diagram. If the inductors are melted we have some we could wind down or up to that value. need to get an idea of what the parts look like though..

ok john thanks, I'll get some pics up soon

[ericd]

soft dome tweeter

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[ericd]

blown crossover pics

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[newsh]

Mmm, the tweet looks like a tiny cone, havent got anything like that. You need to get in there with some test leads though, its possible the series resistor in the crossover has gone and acted like a fuse, you need to disconnect one side of the tweet and measure the resistance (DCR) with a multimeter on a low ohms setting, should be between 6 - 12 ohms ( approx 6 for an 8 ohm unit and 12 for a 16 ohm unit..) If we've got a circuit then its just the crossovers fried and we're in with a chance, if the tweets are open circuit and you cant get a reading we're looking for new ones.
What often happens is the tweets blow when you're ragging the system (no excuse for this as it always sounds really bad before it blows up and you should heed the warning signs ) When the tweets are gone you keep playing the system and all that power goes into the crossover instead and cooks that.

[newsh]

You need to get the crossover board off the back of that plastic thing to look at the components, I reckon you desolder the binding posts and lift it away.

If you take any wires off take a pic or make a drawing of what colour goes where or tape the wires and write on them with sharpie, you want to make sure it goes back together in the correct polarity.

[ericd]

john,

forgot to mention the mid/low drivers are still working , just no high end, I'd unfortunately let somebody play around with them using my old test cd of various things including spot and swept frequency response (2hz-20khz), noise signals etc,etc, once "they" stopped hearing "anything" the amp got turned up and this is the result

[ericd]

little pic of the crossover in question

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[newsh]

little pic of the crossover in question

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Mail me big pics to newsh (at) aol.com