Blown speaker...or what? Help!

Drivers don't shut down, amps do, usually from overheating. Overheating can be caused by a short circuit in the voice coil. It needs to be tested by someone qualified.

 

If you have access to a multimeter, check ohm reading across the terminals. An 8 - ohm speaker should read about 6 - ohms.

GENTLY move the speaker cone in and out and listen/feel for scraping of the voice coil windings inside. Feel / hear anything = bad.

Use a 9-volt battery on the terminals, should move forward or back while battery is attached.

Andy

 

and listen to the smart guys like Bill

 

I've encountered situations where a DCR reading didn't reveal a bad coil. An impedance sweep will. Of course if you get a DCR of zero then it's blown for sure.

 

DCR= DC resistance. a DC reistance reading of 0 ohms means that it's shorted. if it doesn't get a reading, it means that it's open. in both cases, the speaker need to get reconed.

 

No, a 16 ohm load would not hurt the amp. Only going UNDER the rated impedance will hurt.

 

Do tests on good speaker too. and compare.

also amp would 'cut out' with both/either speaker

 

If both speakers work when connected but one makes noise, hook up one at a time and one stops, it is NOT amp shutdown. The speaker that stops working could have a nicked wire in the voice coil winding or poor connection in the flex leads.

Connection from the flex leads to the terminal board are the most likely.

 

Are you testing the speakers independant of the cab ?

Or, are you just "disconnecting" the leads from one speaker and testing the cab with only speaker connected ?

Reason I ask is that it *could* be in the cabs wiring itself (bad solder joint from the crossover, bad connection at the speaker, etc.).

 

You need to look closely at the flexible leads coming from the speaker's cone to the terminal board on the basket.

 

It also may be a cold solder joint on the speaker terminal. Your problem has the same symptoms as a cold solder joint. Although the connection looks good even to a trained eye, it may not be. Try just holding a solderiing iron on the terminal on the speaker where the wire connects to the speaker - A BIG CAUTION - put something underneath the speaker terminals so solder does NOT drop on the cone or it may get damaged. You may want to hold the phone (don't do anything else) and just call Avatar to ask for advice... I hear they are pretty good about. There are other options but from all of the good advice you got here, most everything else is covered.

 

Agreed on checking the tinsel leads, solder joints, etc. It could be that coil got a "hotspot" that doesn't manifest itself until it warms up from playing it. Checking DCR cold doesn't always reveal the problem. You say a terminal is loose on the l-pad. Possible problem there too. If you get the woofer thing sorted out, try running them direct, bypassing the filter/pad/tweeter.

 

Avatars also have an LPF in the crossover. Possible bad solder, cap, or inductor got hot there too. Both woofers test the same. Rig them up to a jack and try playing them without the crossover, that could help narrow it down.