4 ohm Speaker power ratings

[peter460]

I cannot seem to find what the industry consensus is for 4 ohm speaker power ratings . If a speaker has a nominal impedance of 4 ohm and recommended amplifier say is 200w rms does that refer to a 200w /8 ohm amplifier or a 200w/ 4 ohm amplifier ( which usually is equivalent to a 100w / 8 ohm amplifier ).

Anyone know whats normally mean't
Peter 

 

[Rodney_gold]

 

[JimGore]

 

[Byrd2]

 

[chipwelder]

 

[peter460]

 

[Rodney_gold]

 

[chipwelder]

 

[JimGore]

 

[peter460]

 

[chipwelder]

 

[Rodney_gold]

 

[Norval]

 

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