NSD - New Speaker Day and Variac question

[jtcnj]

WGS Green Beret 12", 8Ω, 25w.
I used a variac for break in and let it run about 3 hr.

I am second guessing myself on this. I briefly went by sound and watching the cone excursion, but then measured the voltage at 20v.
20v x 20v / 8Ω = 50w!

I backed it down to 12v: 12v x 12v/8Ω = 18w.
Is this method ok, and is my calc correct?

 

[syscokid]

I used a variac for break in and let it run about 3 hr

I'm really interested on more info (and calculations) on this method of breaking in a new speaker...

 

[Session 5]

Congrats on your new speaker jtcnj. Sweet!

 

[Cadorman]

I thought you had to break in a new speaker with Motorhead?

 

[Amp Mad Scientist]

I thought breaking in a speaker included soaking the cone in beer.
Preferably a good English stout.

The wattage calculation is incorrect.

20 volts RMS AC X current = VA
VA X efficiency = true wattage
This is a true wattage calculation.
Without a number for efficiency, the IS no true wattage number.

 

[jtcnj]

I thought breaking in a speaker included soaking the cone in beer.
Preferably a good English stout.

The wattage calculation is incorrect.

20 volts RMS AC X current = VA
VA X efficiency = true wattage
This is a true wattage calculation.
Without a number for efficiency, the IS no true wattage number.

would that apply to estimating the amount of energy seen on the input to the speaker?
I realize the 8Ω impedance is a nominal number used as R in P= V*2/R, and should I have used RMS voltage instead of measured P-P voltage (20v ac x .707)?

 

[syscokid]

would that apply to estimating the amount of energy seen on the input to the speaker?
I realize the 8Ω impedance is a nominal number used as R in P= V*2/R, and should I have used RMS voltage instead of measured P-P voltage (20v ac x .707)?

 

[jtcnj]

Speaker sounds good; have not been able to really wind it up yet though with family at home.