Speaker Protection Problem

[danbaxtr]

I have an Onix Strata Mini speaker that is causing my NAD M3 amp to go into amp protection at high volumes. What would normally cause an amp to go into projection? The amp worked fine for years with these speakers. I've checked all the cables and connections. It is definitely being caused by my right speaker. Any suggestions would be a huge help.

Thanks,
Dan

 

[ajazz]

Normally every Amp has Over Current Protect to safe guard its output transistors. Just connect speakers of higher impedance than the present one and your Amp won't go into protect mode on high volumes.

 

[ajazz]

or may be one of your speakers coil is about get short (burn out), hence the temporary low impedance

 

[danbaxtr]

The NAD M3 does not have an impedance setting or higher impedance input. It goes into protection on louder passages usually drums. Maybe the speaker coil on the bass driver is the culprit?

 

[planet10]

Sounds to me like a problem with the loudspeaker.

dave

 

[danbaxtr]

Bummer, AV123 is out of business. I believe they used Atohm drivers in those speakers. Could a problem with the crossover also cause this problem? Is there anyway for me to test for low impedance?

 

[Mooly]

Does the suspect speaker trip the other channel in the amp ?

Yes you can measure impedance if you have a meter that reads RMS voltage over a wide frequency range and a signal generator. Check my figures first...
http://www.diyaudio.com/forums/multi-way/121524-testing-speakers-impedence.html#post1488054

 

[danbaxtr]

Yes, if I switch the cable the other channel will trip with the same speaker.

 

[planet10]

Speakers, speaker cable, or connections.

dave

 

[danbaxtr]

Tried different cables, same problem. I also turned off the built in subwoofer on the strata minis.

 

[Mooly]

Yes, if I switch the cable the other channel will trip with the same speaker.

That's proof enough I guess.

I take it the speaker sounds OK in every respect... how about a mono source, is the image central.

 

[ajazz]

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