[RollsDownWindowsManually]

Why is there no standard among headhpne amp producers for power ratings?

For instance, with most home and automotive amplifiers, you will see power ratings at 4 or 8 ohms, 20hz-20khz +/- 3 db, and less than 1% Total harmonic distortion across the spectrum. Most headphone amp producers (headroom, ray samuels, electric-avenues, and even xin) don't have any power output specification. To me, the sound quality of an amp should be a given if the THD is low and the frequency response is broad. The only power output spec I could find was for the heed canamp.

Heed CanAmp: 300 mw @ 100 ohms, <.05% THD, 10hz-50khz +/- .5 db

Since power output is in my opinion, the most important rating for an amplifier, does anyone have power output rating for some of the more popular portable amps @ 100 ohms, for instance say:

Xin Supermicro
Hedaroom Total Airhead
Ray Samuels Hornet
PA2v2

Thanks!

 

[gtp]

Because power isn't everything, and because standardized measurements aren't easy.

 

[nikongod]

there is also no standard headphone impedance. speakers almost always come in multiples of 8 ohms.
0.5, 1, 2, 4, 8ohms etc, etc... all combinations of 8.

headphones who knows...

 

[RollsDownWindowsManually]

Still, if you get the power at a given impedence it's fairly easy to tell what it's going to do at other impedences.....you double the impedence, you halve the power.

Power isn't everything, but power, frequency response (which is almost always flat to within a few db on any decent amp) and total harmonic distortion less than 1% pretty much should.....

I think power should be pretty important, especially when you're talking about 300 ohm sennheisers and whatnot.....seems like you'd need a good bit of juice for those, and it'd be nice to have a spec for comparison's sake.

 

[nikongod]

Quote:

Originally Posted by RollsDownWindowsManually /img/forum/go_quote.gif Still, if you get the power at a given impedence it's fairly easy to tell what it's going to do at other impedences.....you double the impedence, you halve the power.

unless you are running an OTL tube amp, in which case the high impedance headphones get MORE power than the lows.
Quote:

I think power should be pretty important, especially when you're talking about 300 ohm sennheisers and whatnot.....seems like you'd need a good bit of juice for those, and it'd be nice to have a spec for comparison's sake.

i disagree with power requests. a single chip cmoy with gain of 10 will drive almost ANY current production dynamic headphone to levels that show "questionable safety" for the people 3 ft away... on the outside. this is not to say anything about SQ in the experiment above, because it will likely suck, but it clearly exceeds "necessary power."

the real trick has very little to do with power at all. the real queston is all how it sounds.

on that note the idea of measuring THD and noise and the like comes up. eeh, its a weighted measurement still. somehow there are all these amps that measure like a brick made of poo (1%thd) that sound better than "perfection to 0.001%thd" amps.

somewhere in the middle, at some balance point is a place where the amp "is" for you. this is not unlike ice cream. some people like vanilla. some like mint-chocolate chip. some like chocolate. some like rocky road. some are crisp, some are smooth, some are VERY thick and heavy. but you can easily mix at least a little bit. nobody looks at you funny for asking for vanilla and chocolate icecream on a cone.

i myself try to have a pint or 2 of each in my freezer at all times.