[cactus_farmer]

I'm limited on funds right now, I had no headphone amp at all (not even something like a hifi receiver as I don't own speakers) so I quickly bought a Fiio E5 to use through an iPod Classic's line out dock as a temporary solution to power my HD650.
 
However, because the Fiio E5 is such a weak amp (although it is rated as being able to power 16-300ohm headphones - many people say that you should ignore this statistic) could it be damaging my HD650 headphones by straining itself to drive them to appreciable volume levels - thus resulting in clipping which could burn the voice coil?
 
Because the Fiio E5 has no volume wheel - only '+ and -' buttons - I have no idea how much I'm pushing the little amp! Should I just not use my HD650 until I get a proper amp to use them with? The problem is that the damage might already have been done...

 

[JoetheArachnid]

I don't think there's a way to damage voice coils by feeding them 'too little' power. If you can't hear clipping then it's probably not clipping - I'm not sure that an E5 fed with an iPod LO can clip anyway.
Stop worrying. It actually takes quite a bit to damage a voicecoil - you'd need to put a good few watts through them consistently to burn them up. The E5 is providing nothing like that, clipping or no clipping.
 
In the meantime, save up and buy a decent amp to power your cans. I think I can say without doubt that the tiny FiiO isn't showing their full potential.

 

[cactus_farmer]

I thought it was a common misconception that a 'too powerful' amp damages headphones, rather it is UNDERfeeding them with too weak amps that does the damage. I thought that with amps, the more power the better, no exceptions?

 

[JoetheArachnid]

Not entirely sure where you got that from, especially the bit about 'the more power the better'. Most headphones (ignoring the likes of K1000, orthodynamics, electrostatics etc.) can take a maximum of 200mW (some a lot less) before you start damaging the driver. So running, say, a PX100 out of a power amp that can put 100W into 8 ohm speakers would put 25W through those tiny drivers. Then you can only actually use 0.8% of the power available before blowing the drivers, which in itself doesn't give you much room to work with in the way of volume control.
More power is good, but only up to a point - the popular Schiit Lyr can put 6W RMS into 32 ohms, which is totally fine for orthodynamics and some higher-impedance cans that need a lot of power, but you equally wouldn't use it with sensitive IEMs. It's about matching the power provided to the task at hand rather than more simply being better.
 
And if you think about it, if underfeeding heaphones damaged them, then any low-level music or hum would actually damage headphones and so they'd have to be either playing loud music all the time or be unplugged to last. That's obviouly not correct.

 

[ClieOS]

...and some say driving a Ferrari too slow will cause the engine to burn out

 

[cactus_farmer]

No, as I understand it, a weak amp damages headphones if you try to push it harder (volume wise) than it can go. If the amp is VERY weak, 'pushing it hard' may not even be as loud as an acceptable listening level. And once the weak amp is struggling it sends out clipping and distortion which melts the voice coil on your headphones - and, again, if your amp is very weak - this can all be done at a very low volume level.
 
So in this situation your headphones were damaged because your amp wasn't powerful enough to do it's job properly.
 
A very POWERFUL amp can only damage a headphone if it makes your headphones go so stupidly loud (you'll lose your hearing way before this level) that the driver starts to tear away from its housing or something.
 
So in this situation your headphones were damaged because your amp did it's job TOO WELL and your headphones couldn't handle it.
 
The Fiio E5 definitely fits into the 'too weak' category of amps. As I said, since the Fiio E5 does not have a volume wheel and only volume buttons, you cannot tell at what '% of the maximum volume it can reach' that you're listening at. I just plug in my HD650 into it and press the '+' button on the volume controls until it reaches what I think is a good listening level. If there were a volume wheel on the Fiio I might discover that the wheel was turned almost all the way clockwise at my 'good listening level' and thus the Fiio was struggling, nearly maxed out and sending out clipping and distortion to my HD650. Because there is no wheel I can't tell if it's nearly maxed out or not. Therefore I can't KNOW whether or not it's damaging my headphones... Does that make sense?

 

[JoetheArachnid]

According to the official specs, the E5 can put a paltry 16mW into 300 ohms. That is nowhere near enough power to burn the wire in a voice coil under any conditions, especially when fed only by an iPod LO.
 
I also understand that the E5 has 20 volume steps, so try turning it down as far as it can go (press the '-' a bunch of times) and then count the number of '+'s it takes before you get to a comfortable listening volume. Again, if it were clipping or distorting in the way you describe, i'd hope that you'd be able to hear it. As things stand, you might get some clipping at the highest volumes, but this would be due to a deficiency of power from the E5 rather than damage to your Senns.

 

[cactus_farmer]

Yeah but as I outlined there are two ways of damaging the headphones;
 
1). MECHANICAL damage by having a massively powered amp drive them too loud
2). THERMAL damage by having a weak amp struggle and produce clipping
 
Weak amps can produce damage type 2).
 
I copied this from another forum;
 
"basically, a clipped signal will cause a speaker to reach its thermal limit using a lot less power than it is rated for/should be able to handle. the energy from the clipped signal builds up in the voice coil in the form of heat, and since the speaker isn't moving in its full motion, it can't properly cool itself. thus, the thermal limit is reached, without overpowering the driver."

 

[JoetheArachnid]

If you're really totally convinced that the E5 is damaging your headphones, then don't use it. It's that simple. You seem to have made up your mind already, so I'll leave you to it.

 

[cactus_farmer]

Thing is that E5 is my only option as I don't own an amp right now. Turns out that I was using it at it's max volume (20/20). Couldn't hear anything that sounding like clipping but then again I've never heard clipping so i don't know what to look for. Also as I said earlier I listen to a lot of experimental electronic music so I don't know what weird beeps, blips and sweeps are meant to be in the music and what is actually clipping.

 

[jackmccabe]

There is now way a fiio e5 could damage the hd650's, you are talking about when an amplifier begins to clip and produce's massive bursts of power at certain frequencies.
Plenty of people have used the fiio with the hd650's and been fine, so stop trying to persuade yourself that it will damage them.

 

[Blasto_Brandino]

Save your pennies, buy a UHA-4, drives the HD650's so well, sooooooo well....

 

[qusp]

not entirely true according to some opinions and some experts too little can indeed cause some damage, because when some amps clip, they produce dc. in this case it wouldnt be very much dc and there is some controversy about this anyway, but possibly not to be ignored. if a preamp clips it is just the waveform being chopped off, but when the amp driving the load clips it can cause damage to the voice coil. i find it a bit odd personally too, but its not an uncommon idea.

 

[ClieOS]

Quote:

not entirely true according to some opinions and some experts too little can indeed cause some damage, because when some amps clip, they produce dc. in this case it wouldnt be very much dc and there is some controversy about this anyway, but possibly not to be ignored. if a preamp clips it is just the waveform being chopped off, but when the amp driving the load clips it can cause damage to the voice coil. i find it a bit odd personally too, but its not an uncommon idea.

Even if that is true (clipping causes DC), then it won't matter to E5 anyway since there are coupling caps inside.

 

[JoetheArachnid]

Also the fact that even if you took out the E5's battery and ran the DC terminals straight through the voice coil it probably still wouldn't burn them.