Axiom Home Page Forums General Discussion Home Theater Is my hk powerful enough

I think we need some equations here.

Brownies + chocolate frosting= happy stomach.

For all interested, see section 5.

http://www.hps4000.com/pages/digital/powering_up_for_digital.pdf

Ken, lets try the form of Ohm's Law relating power to voltage and resistance: P=V(squared)/R. So, 1(watt)=2.83 volts(squared)/8ohms. Any number of watts or volts can be used in the measurement as long as the result is stated in terms of the usual standard, equivalent to 1 watt.

ohms law is one of the very few things I actually remembered from my electric circuits class. Still haven't figured out why that class is required for civil engineers...?

On the fundamentals of engineering exam I could answer all of the ohms law problems and converting resistors in parralel and series into single eq. resistor easily

Anything that said AC and had a sine wave I guessed c!

Why did I have to take mechanics and dynamics (which I loved by the way)?

Rick, my cheap and dirty way of measuring sensitivity here at home is to inject a 50Hz signal into the M80 with a 2 Volt average value and then measure the SPL. Why 2 Volts? Because at 50Hz, the M80s impedance is bang on 4 Ohms according to the charts. 2V across 4 Ohms yields a power of 1 watt. (To verify that this is indeed the impedance I could measure the current but I haven't done that.)

Now as I'm writing this I'm thinking that perhaps 50Hz is not a great value for rooms like ours. I should probably use 500Hz or above to get away from room effects.

Anyway, an important point here is that Soundstage averaged the SPL from 300Hz to 3KHz. What frequencies did Axiom use? Maybe Axiom went down to 80Hz which is approximately the limit of anechoic chambers. Axiom did their tests anechoically; did Soundstage? Or did they do them semi-anechoically?

Right, got it.

I always thought the tests the were usually done with a 1khz signal?

Ok, though I didn't have a lot of coffee this moring I think the article from EFalardeau and Johns explanation clears things up. It isn't a matter of the numbers used as long as the end result equals 1w @ 1m and this can be done in a number of fashions.

Exactly. Coffee sounds like a good idea, actually. I think mine is ready! (BTW, it is now officially winter in Montreal; we are having our first snow storm... too bad I am running out of excuse to stay home with my speakers... kidding! I still have plenty of excuses).