Blown speaker, again!

[JoeTV]

I had a blown speaker in December. The woofer was frozen. Tweeter replaced it under warrenty. Last night, while listening to music (in 4 ch stereo mode), I noticed the same speaker sounds distorted again! I have not had the volume up very loud. Is it possible the crossover in the speaker is defective (it was not changed or repaired in Dec), or could it be a channle in my amp? I have swapped cables from pre/pro to amp and switched left and right, it is the speaker.

Thanks for your help.

Joe

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Mitsubishi WS55807

Zenith DTV1080 (RS Double Bow Tie Ant)

B&K REF 30 Pre/Pro

B&K AV5000II 5 ch Amp

Tributaries High Performance OFHC 12AWG Spkr Wire

Klipsch RF3-II (Main)(bi-wired)

Klipsch RC3-II (Center)(bi-wired)

Klipsch RS3-II (Rear)

SVS 25-31PC+(SUB)

Sony 300+1 disc Prog Scan DVD

Sony 300 disc cd

Sony MD (for sale)

Sony cassette

Pioneer 563A (for DVD-A & SACD)

Mitsubishi S-VHS

ProntoPro

Antique 1973 turntable, still works great!

Home-made oak cabinet

[doudou]

it might be the wires running from the crossover to the speaker...

you can open your speaker to check if the crossover or the wires looks fine or not.but if your speakers are still under warrenty you should make work it and don t open your speakers because it can broke the warrenty.

[JoeTV]

Thanks,

It is under waranty, I will let Tweeter check it again...

[D-MAN]

There are 3 possible causes that I can think of that may put some light on this:

1) overdriven (you)

2) amp channel is bad (amp)

3) quality of driver in question (them) including "over-rating" or improperly spec'd

Assuming that the speaker is rated at well under the wattage being used, woofers typically handle the most wattage in an speaker array. The crossover has ONLY to do with a woofers high frequency rolloff in matching it to the midrange crossover point, i.e., without a crossover, the woofer will rolloff naturally at its high frequency limit even with no crossover as it simply cannot physically move fast enough to reproduce higher frequencies; the physics involved will not burn out a woofer as higher frequencies take less wattage, and so forth. If the crossover had a direct short in it, the speaker would not make any noise at all and the amp channel would probably fry; if it was open, again no noise, but the amp channel would be unaffected. The fact that you can still hear noise out of it is indicative that the crossover is more or less intact. So I would doubt the crossover as having anything to do with a woofer frying or becoming otherwise "stuck". Remember, we are only talking about the woofer here...

You reported the first time as being "frozen". This can be from either a voicecoil frying to the magnet structure (from exceeding the wattage capability of the driver) or from a physical cone/capstan alignment failure.

The report of distortion indicates excessive excursion (in my estimation) or a mis-alignment of the capstan/spider/cone elements. There may be rubbing of the voice coil on the magnet structure, etc. This is indicative of (a) poor quality control, ( mislabeling causing one to believe that the wattage levels are safe when in reality they are not, or © excessive cone excursion do to overdriving. It doesn't matter that it is not being overdriven NOW, only that it occurred to a damaging point in the past causing mis-alignment.

Not knowing the rated wattage capability of the driver in question, I would go for the excessive current theory, too much wattage. Only a physical examination of the problem driver would tell you where the problem really lies.

On the other hand, it could be a problem with the quality control of the driver manufacturing itself. This includes the quality and type of glue employed, and the care in alignment and even the storage and shipping that the driver has been subjected to. Typically the manufacturer is not going to admit to the consumer that the speaker drivers may be inferior in any event, although they probably know due to other warranty repairs being made. In such a case, there is nothing that you can do except demand your money back and see what happens.

Good luck,

DM

[michael hurd]

Hmm... I have not suffered any blown drivers, and I have certainly driven my speakers hard at times. Not to say that it can't happen, as we all know that there is really no such thing as bulletproof. This being said, as a sad fact most newer modern recordings are highly compressed, bringing up the average levels so high that there is almost no dynamic range left. This can lead to problems when speakers are driven very hard. It sure seems odd that the same speaker sounds distorted. I would have the amplifier checked out for sure.

[lynnm]

Craig turntable (Antique 1973, still works great!) ............... J. Zuss your making me feel old here bucko ! I was 30 when that TT was manufactured!

I'm betting against your amp here. One speaker on one side of an amp can easily be put down to bad product,luck etc. Two speakers and I'm beginning to smell a rat .......errum an amp that is suffering from some sort of nasty problem and sending pure D.C. to the speaker when it acts up. I would get the driver replaced under warranty but also get that amp checked out because I wouldn't trust that thing as far as I could throw my Brother-in-law ( Not that I could catch the bugger he's likely too fast for me!)