how much power do you need two drive magnpan1.6s

Eldartford ...

I actually made some measurements while my MG1.6 was playing very very loud music.

How did you do this? I would love to know what my speakers are demanding during my play.

Rockadanny...I simply used a digital voltmeter, which makes a measurement about once per second. Careful observation will yield a result very near the maximum brief rms voltage. Then the peak is reasonably estimated as 1.4 times the rms. A peak-reading meter would be better, and an oscilloscope would be best.

Good experiment with some measures.
Now that I think about it....a speaker with a hi-powered amp can see 2x the voltage I mentioned....an amp typically has 2 power rails....plus / minus so the difference between the rails is what the speaker sees.
My International Rectifier class 'd' (for play) has 2 rails with a max of +/- 55v.

What happened to P=IE? By this method.....the max current to the panel (fuse limited to 4 amps, 600hz and up) is as I wrote in my last post.

My Formula, and yours are both correct...My assumptions couldn't be right.

http://www.the12volt.com/ohm/ohmslaw.asp

So I suspect I made a bad assumption of voltage to the panel.
Fact is, the darn thing has a 4 amp fuse which sets an upper limit on amp current, No? If the panel can sustain double the fuses rating and as know, is pretty flat at 4ohms....with a nasty peak at the 600hz x-over, that should set an upper limit to power. The Panel maxes out at about 18 ohms at 600hz and over 6 ohms from 200 to 2000 hz.

Other than a math problem, What is the problem with the rest of my post?

Also, now that I look at an impedence / phase chart of the 1.6, I realize that even for this speaker (fairly benign), the problem is pretty complicated. If you take the 18ohm at 600hz, and ASSUME a max of 5 amps at that frequency, that is Isq=25 x 18ohms = 450 watts at 600hz. Even 7 amps yields 'only' 882 watts....clearly a deal breaker at that frequency. it gets weird when considering music.

http://stereophile.com/floorloudspeakers/595/index6.html

If I had the time/tools ( I am immediately sending away for a Kill-A-Watt.....<20$@newegg) I will measure the entire power needed by my fairly efficient GCC250......than use some kind of fudge factor to determine power to the speaker.
The neighbors have aloud treat instore for them.....!

Thanks, Eldartford for making me rethink this. My conclusion, however, remains the same. It is very likely that Hi-Current is a Magnepan red-herring, given the limits imposed by the fuse and physics....

Magfan...True that Watts = E * I,

But I = E/R

So Watts = E * E / R.

Also, the "rail" voltages get output one at a time. PlusV-to-ground OR MinusV-to-ground. Never PlusV to MinusV.

Also, the 4 amp fuse is at 120 volts. It can yield much greater current at the lower voltage delivered to the speaker via the amplifier.

Eldartford, is this a test? Sorry, but as near as I can determine, a fuse can be used at any voltage below its rating.
In the 'hydraulic' model, volts is pressure and amps is a quantity....somewhat independent.
If your contention were true, the fuse would provide little or no protection, since you could somehow devise an amplifier which would output very low voltage @ very hi current, and still be within your definition of a fuses ratings.
A fuse doesn't dissipate 'watts'...

My bad with my first post was poor choice of numbers.
I still maintain that hi-current to maggies is somewhat of a red-herring.
Please design a scenario where a maggie can receive say...20 amps at whatever voltage you choose. Than, find me an amp that produces such and not 'pop' the fuse.
Also, with the voltage rails at +- a (given) voltage, this represents the maximum voltage the speakers can see. The absolute value of +-50 volts is 100v Without Sign. (absolute value definition)
The only thing left to argue about is 'how large a spike a fuse can take over what time period'
http://www.circuitprotection.ca/fuseology.html#Top
Link has useful chart and definitions. Go to the bottom of the page and look at 'Voltage Ratings'...that a 250v fuse can safely be used in a 125v circuit negates your arguement.