[koven]

Long story short, I bought some speakers that were shipped to me. When they arrived, one of the tweeters was completely silent, no static or hiss.

I asked the seller about this and he said it must be shipping damage, and that it was fully functioning before he sent it out. The packaging actually seemed decent and there's no physical damage on the speaker. Could the shipping have loosened up some wires in there or is it unlikely? For some reason I have a feeling he knew the tweeter was dead, but sold it anyway.

 

[Uncle Erik]

The seller could very well be honest. Many speakers have internal connectors that slip over the contacts on the driver. Those can be knocked loose without visible damage to the speakers or packaging.

If you have a screwdriver handy, unscrew the tweeter and make sure that both leads are connected. If one is loose, just push it back on. You'll understand immediately when you see it.

Another possibility is that a drop/bump knocked a solder joint loose in the crossover, shorting out that tweeter.

If you have a DMM, you can test to seeif anything is coming through at the tweeter outputs on the crossover. If nothing comes through, then the fault is in the crossover.

Also, you can use a DMM to measure conductivity across the tweeter. If it conducts, then it's fine and the fault is in the crossover.

Another way you can test (assuming that the tweeter leads slip on and off) is to swap the tweeters between channels. If the "dead" one works in the other side, something is wrong with the crossover. If it doesn't work, then the tweeter is bad.

I am hoping that one of the contacts simply slid off in transit. Please check it out and let us know.

 

[koven]

Both leads were connected, I disconnected one lead and measured the resistance with a multimeter and it's reading 0 ohms. I also swapped the other tweeter in, and it's working perfectly. So I'm pretty sure the tweeter is dead. Not sure how it could have happened in shipping though.

Anyway, I'm going to buy a replacement. My question is, should I just replace both? Does it matter much if the tweeters are "matched"?

 

[Uncle Erik]

Sorry to hear that, I was hoping it would be an easy fix. It's possible that the lead to the voicecoil got detached in shipping. Were they insured? Insurance might pick up the cost of repair.

As for matching, ask the manufacturer or whoever sells replacements. They should know. If you're buying from Madisound or Speaker City USA (I have bought from and recommend both), they're very helpful.

 

[JaZZ]

Quote:

Originally Posted by koven /img/forum/go_quote.gif Both leads were connected, I disconnected one lead and measured the resistance with a multimeter and it's reading 0 ohms.

Which means it's short-circuited. Or you have chosen a scale where resistances above 200 ohm aren't displayed. A short-circuit is very unlikely on a speaker driver, except for the case of a melted voice-coil. Is there a way to inspect it? You would have to remove the driver's front plate. Another possibility is a break on one of the fine leads between the driver's soldering flap and the voice-coil – which would be hard if not impossible to fix (and most likely can't have happened during transport).
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[tjohnusa]

If the tweeter is 0 ohms then the voice coil is open and not shorted. What make and model are the speakers?

 

[JaZZ]

Quote:

Originally Posted by tjohnusa /img/forum/go_quote.gif If the tweeter is 0 ohms then the voice coil is open and not shorted.

What do you mean by «open»? A short-circuit makes for almost 0 Ω, whereas a broken wire measures ∞ Ω, which can't be displayed, so the display says...(«0»?)? -- It's been a while since I've been into speaker building, so first I thought you could be right. But at least my own multimeters all show an empty display in this case. «0» is displayed when the measured resistance value falls below the resolution of the chosen range.
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