You can use a speaker with 4 wires. Output tube B+ and one field wire would be tied together. Original speaker had a field coil of 460 ohms. Should find a speaker with similar resistance coil or use a PM speaker with wire wound resistor for the field.
Norm
:Model E-106,Rider 7-29. The speaker is missing,uses the type with 3 pins, is there a way to use the more common speaker with 4 pins??
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