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How to test an old speaker?
#1

I've got a couple of very old speakers that I would like to test. One is the horn style (I think it is a radiola) and the other is the round kind. I don't have a 1920's radio to use for testing. Is there a way I can hook these old speakers up to something to safely test them?

The artist formerly known as Puhpow! 8)
#2

For the old speakers (like horns) we just used a nine volt battery and listened for a click. Often the old wires are bad so test right at the driver before you rule it bad.

If you're at home you can hook an audio source to it, but you'll probably need to do a little impedance matching depending on your audio source.

John KK4ZLF
Lexington, KY
"illegitimis non carborundum"
#3

Use a spare output transformer. Connect the low impedance side to any 8 ohm speaker jack.
#4

Thanks John and Sky. I'll try to post a couple of photos later. I don't really know anything about the 1920s stuff. I didn't want to do anything to damage them.

The artist formerly known as Puhpow! 8)
#5

If they're in decent condition at all, the coil should be very high impedance and not easily damaged. They were dropping many times more than 9 volts in the original radio.
#6

Not sure what he had in it but a man at the museum has an altoid can with headphone jacks on one side and the 1920's pin jacks on the other so he can test/listen to horns using his iphone, walkman, etc. so whatever he uses is small enough to fit into the altoid tin.




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