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

Magfan...If we use 6 ohms (as you do) I agree with your 400 watts. However, I was under the impression that MG1.6 were a pretty flat 4 ohms, and resistive to boot. Using 4 ohms and your 50 volts gives 625 watts.

A fuse blows because of I*R heating. Voltage doesn't matter. How long it takes to blow a fuse depends on how high the current is. The rating of a fuse, eg: 4 amps, is the current it will carry forever without blowing. Most fuses actually carry about 1.2 times their rating for quite a while, and twice their rating briefly. "Fast blow" and "Slow blow" fuse types are designed to modify these typical characteristics.

Eldartford, please check out the Stereophile review I linked a few posts back. The Maggie is INDEED quite flat at just over 4 ohms. Only fly in the ointment is the 18ohm peak at the 600hz x-over and the fact that it is 6ohms or better from 200hz to 2khz. This is, of course, a very important area for music where much of the energy resides. Phase angles are also highest in and near this range. Let's not go into that! We are dealing primarily with good quality amps here and these numbers should present no problem to the grade of amp a Maggie owner would typically buy.....agreed?

Agreed about fuse and ratings and actual capacity. This is addressed in the other link I provided. There is a 3rd catagory of fuse....a Really fast blow. This element has slightly higher resistence that the std fuse, but I know nothing past that. Maybe for use in very critical applications and 'delicate' circuits?
The fact that a fuse is not a 'brick wall' device probably means 2x power, short term or 3db. And, since R (impedence, in this case) is 'fixed', it's gotta come out of the IE part of the equation...You can only get so much voltage from an amp, limited by the PS, so amps it is!

No wonder my electric bill has skyrocketed.

I threw a dart and chose 6 ohms. YMMV, of course.
I believe you were on to something a few posts ago. MEASURE is the way to figure this out. Since music is very complex, there are no easy answers. A string quartet and pipe organ played at a similar spl should have drastically different power requirements....

But, for Pete's sake, how loud do you want it? I must be getting old, but I give up somewhere south of NoseBleed!

Please post some more measures.............

thanks guys for all the info I have my maggies hooked up i am realy happy with them i find that the two ohm taps on the mac mc352 work the best it just sounds better to me than the 4 ohm tap the music is more detailed thanks ALL very much majic

I have some experience with really, really, realy, fast fuses! They were to protect transistors in a very expensive and hard to repair motor drive circuit in a missile guidance system. Turns out, there are fuses that are fast enough to protect transistors, but they are themselves transistors, and they cost more than what they protect. It was worthwhile in this case to use the fuses because the cost to repair a blown circuit, reassemble and retest the guidance system would have run to tens of thousands of dollars. Better to replace the thousand dollar fuse.

Magfan...Interesting about the impedance plot of the MG1.6.

I did an upgrade to the crossovers in my MG1.6...same design just better parts, like air core inductors. I was surprised to find that the high and low frequency crossover slopes were not only different, but the crossover frequencies were significantly different also. I seem to remember that the LF was electrically rolled off well below where the HF cuts in, and this would result in an impedance increase through the gap. Magnepan does a lot of proprietary tweeking to achieve flat frequency response, and the crossover design is part of it.

This is why I have serious doubts about the wisdom of biamping Maggies using an electronic crossover.