tube watts vs transistor watts?


I have always been told your loudspeaker does not need as many tube watts as transistor watts. Why? If the loudspeaker manufacturer says it takes 200 watts for power handling how many tube watts does it take?
seadogs1
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Tvad, it's possible for a given speaker to have both a low nominal and minimum impedance.
xti16 - as to your reference to power calculations, it makes no difference which form of the equation you use, they are synonomous. To state otherwise ignores ohms law.
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