Audio Systems: Car Speaker, ohm speaker, power resistors

Question
I have a car from the 60's with the original AM one speaker radio. The speaker is 8 ohms. Is there any problem using a new 4 ohm speaker? Can the radio be damaged?  

Answer
Don,
You cannot connect a 4 ohm speaker to the older radio, if you do the output transistor will burn up!, however you can put in series with the 4 ohm speaker two 8ohm 10 power resistors paralelled together and the impedence will be 8 ohms.

TOM,
T&D ELECTRONICS
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