OVP on the Outputs?

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OVP on the Outputs?

Postby jwhitmor » Sat Feb 07, 2015 1:23 am

There was a reccomendation (elsewhere) to put overvoltage protection on the outputs connected to the speaker terminals. The suggestion was to use two 35V zener diodes. The hope was, that it would save the output transformer if the speaker circuit opened up (some speakers are fused). Is this snake oil? Would it have a sonic impact? I don't remember seeing this in a schematic yet, but I have seen plenty of warnings not to crank the amplifier without a load attached. What is your opinion on this?
Thanks,
J.W.
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Re: OVP on the Outputs?

Postby battradio » Sat Feb 07, 2015 3:10 am

That might save the speaker but would be rough on the output transfomers if they shorted . A 100 ohm 10 watt resistor across the output would be better
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Re: OVP on the Outputs?

Postby jwhitmor » Sat Feb 07, 2015 1:07 pm

My thoughts were along the same lines,. If you were using something like a heavy duty zeners back to back, better put a 6 to 10 ohm power resistor in series with them. The more I thought about it the less I liked the idea.
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