Upset

[tdelahanty]

The tweeters seem to have gone bad in my Olympica 3's. Have to send them back before SF will send new ones. SF told my dealer they have never had these tweeters go bad. If they don't honor the warranty it will cost $1000.00. Mostly I listen to jazz at moderate levels, they have never been stressed.

[Yamaki]

Wow! Sorry for your troubles and good luck with the resolution.

[Cohibaman]

Very strange that both went out when only listened to at moderate levels. Have you measured the DC voltage coming out of your amp?

[scirica]

That does seem odd. Hope you figure it out quickly! Good luck.

[AudioGremlin]

Yes I was wondering that too, its certainly worth checking the offset voltage at the amplifier output. Depends too if theres a capacitor in series with the tweeter to block the DC from the tweeter.
I recall an unfortunate customer (when I was in the audio business) that burnt out his tweeters by playing a frequency band test CD, the frequency played was higher than his hearing ability so what does he do... he turns the preamp gain up to maximum and eventually detects a burning smell. Not recommended.

[tdelahanty]

Audio Solutions lent me a pair of Thiel 1.6's, they sound wonderful, there is nothing wrong with my amp. If the amp was outputting DC it would show at the woofer not the tweeter, there are caps which divide the frequency band, thus blocking DC to the tweeter. High enough DC would shove out or suck in the woofer depending on its polarity.

I can think of three things which might have damaged the tweeters. 1) I was listening during a storm last week, 2) our electric company switches providers at midnight and there is a momentary spike, 3) I wonder if the smoke generated by our model trains has damaged the tweeters. The fluid seems to be some type of scented oil that is heated and vaporized by a smoke generator in the engine.

[Cohibaman]

Originally Posted by tdelahanty

If the amp was outputting DC it would show at the woofer not the tweeter, there are caps which divide the frequency band, thus blocking DC to the tweeter. High enough DC would shove out or suck in the woofer depending on its polarity.

Depends on the crossover network. It'll cost you nothing to measure the output to be sure.

[tdelahanty]

Originally Posted by Cohibaman

Depends on the crossover network. It'll cost you nothing to measure the output to be sure.

No DC offset (measured with Fluke 87 dvm)

[AudioGremlin]

Its highly unusual for more than one tweeter to fail. I know this scenario is highly unlikely in a modern power amplifier but one other reason I can think of for more than one tweeter failing would be amplifier HF instability known as parasitic oscillation. I suppose a large amplitude HF spike due to a mains or lightening anomaly could possibly also damage tweeters.

[tdelahanty]

Originally Posted by AudioGremlin

Its highly unusual for more than one tweeter to fail. I know this scenario is highly unlikely in a modern power amplifier but one other reason I can think of for more than one tweeter failing would be amplifier HF instability known as parasitic oscillation. I suppose a large amplitude HF spike due to a mains or lightening anomaly could possibly also damage tweeters.

A mains spike/surge is the most likely culprit. Our power company does not produce its electricity, they purchase it off the grid. Every night about midnight they change providers and there is a momentary glitch. I have decided to leave my amp in the standby mode in lieu of full-on.