[jacdan]

The Beyer DT770/Pro 80s have a rated PHC of 100mW. If a given amplifer has a power output greater than 100mW at 80 ohms, would that damage the drivers of the 770s or is this a gross misunderstanding of how PHC works? The power output of amplifier is:

300 ohms: 187mW
32 ohms: 500mW

 

[cswann1]

The power handling of headphones is a mystery to me too.

How a company arrives at a number to put on the spec sheet is probably based on some sort of controlled and scientific testing. But I pay absolutely no attention to this spec.

As long as you are not driving your phones to the point of distortion or amplifier clipping, you are likely not in any danger of blowing out a driver.

Some folks love to listen at volumes that risk damage to their ears (I've seen it first-hand at a Head-Fi meet), so for those folks this rating is probably more important. I listen at only moderately high volumes, and if I do crank it up, it's usually for only one song.

 

[jacdan]

Quote:

Originally Posted by cswann1 /img/forum/go_quote.gif As long as you are not driving your phones to the point of distortion or amplifier clipping, you are likely not in any danger of blowing out a driver.

That's the thing though, could high power output from an amp damage the drivers regardless of the volume output? Since I see this distortion problem with 770s mentioned often in threads on this forum, I was wondering if that could be caused by excessive power from the amp damaging the phones. 100 mW is pretty low for closed headphones, I think. I read somewhere that 1000 mW should be the minimum for closed cans.

 

[sunseeker888]

The way I see it is that the manufacturer lists the maximum input level simply as a reference. Go by what you hear. Since even the cheapest, worst can you can find will likely be pretty loud before it burns up, you're fine. You can never have too much power for a dynamic speaker or headphone. Just watch the volume.

 

[obobskivich]

Quote:

Originally Posted by sunseeker888 /img/forum/go_quote.gif The way I see it is that the manufacturer lists the maximum input level simply as a reference. Go by what you hear. Since even the cheapest, worst can you can find will likely be pretty loud before it burns up, you're fine. You can never have too much power for a dynamic speaker or headphone. Just watch the volume.

exactly

the headphone/speaker only takes what it "needs" relative to where you've got the volume set (does that make sense?)

I've hooked pretty cheapass stuff up to 50-60wpc amplifiers (we're talking headphones or computer speakers, raw drivers) and run the thing up to 100% output (like beyond clipping at 60wpc into something rated for maybe 60 mWpc), it still takes a while before the driver actually "melts down" or "pops"

not to mention that 100 mW into your DT770's would probably pop your ears before it'd pop the cans

(and afaik 100 mW is "maximum sustainable input power", just like ratings on speakers are stated "maximum input power", peaks can usually be higher, momentary can usually be higher, etc, because you're talking about instantaneous bursts (which don't heat things up or force too much excursion, in theory))

 

[jacdan]

So, in other words, nothing to worry about

. Thanks for the info everybody.

 

[obobskivich]

Quote:

Originally Posted by jacdan /img/forum/go_quote.gif So, in other words, nothing to worry about

basically

happy listening

 

[DarkBeyer]

thank god!
i was very worried about my new beyerdynamic 770 pro 80!
as long as you hear at moderate high levels with no distortion your can will be just fine!
great post

 

[DarkBeyer]

thank god!
i was very worried about my new beyerdynamic 770 pro 80!
as long as you hear at moderate high volume levels with no distortion, your cans will be just fine!
great post

 

[Uncle Erik]

What you need to keep in mind is that a 500mW (for example) amp does not continuosly put 500mW into a pair of headphones.

To get 500mW, your source would have to be at maximum output and you'd have to crank the amp all the way up. 500mW is the maximum output.

Most of the time, it'll only output a fraction of that amount. If you have the volume at 20% and the source material is fairly quiet, a 500mW amp might be loafing along at 40mW.

This is why it's generally OK to "overpower" headphones and speakers. You shouldn't worry about it.