5E3 output jack connected to ground with no speaker attached

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radu5er
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5E3 output jack connected to ground with no speaker attached

Post by radu5er »

Can someone explain to me why the output jack on a 5E3 amp is switched to ground when there is no speaker attached?

I know it's not a good idea to run an amp with no output load but why is it shorted to ground with no speaker?

Thanks in advance for the info... :?: :?:
TUBEDUDE
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Re: 5E3 output jack connected to ground with no speaker attached

Post by TUBEDUDE »

Because of the two options, a short is less likey to destroy the output transformer than an open. Ideally, if the speaker is unplugged the output would be dropped across a load. I find a 27 ohm 15 watt resistor to give peace of mind.
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radu5er
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Re: 5E3 output jack connected to ground with no speaker attached

Post by radu5er »

Thanks T-Dude, I thought it must be something like that but I didn't understand why they weren't built with some kind of load to be switched in rather than just grounding the secondary. Probably had to do with the company accountants. I have a few 8 ohm 50 watt (allegedly) resistors in the junk box...I'm going to install one of those I think to switch in, in case the the speaker is pulled.

Thanks again man!
Stevem
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Re: 5E3 output jack connected to ground with no speaker attached

Post by Stevem »

You also want to protect the amps OT in case the speaker itself goes open while you are playing and to Kill two Birds with one stone just solder in a 250 ohm 7 to 10 watt resistor across the output jack and call it a day!
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