[stchenhua]

I just compared the harmonic distortion graphs of armature driver iems with dynamic headphones on headphone.com, and it seems that all the armature ones available on that site have much worse distortion than dynamic ones. Does anybody have a reasonable explanation on that?

You can check, for example, the graph of HD650
=255]http://graphs.headphone.com/graphCom...phID[]=255
compared with UE triple fi 10 pro
=675]http://graphs.headphone.com/graphCom...phID[]=675

 

[b0dhi]

+1. There was a thread on this a while back, but I don't think anyone knew why. If anyone can shed some light, I'm all ears.

 

[stchenhua]

bump for more discussion

 

[TMM]

could be due to the test setup headroom use?

also, i wonder if all the peaks in distortion are due to the 'tunnel' effect of IEMs, and it is the resonant frequency and all the harmonics that make up the peaks.

 

[b0dhi]

It can't be their setup because only IEMs have the extra harmonic distortion. I'm pretty sure they use the same in-ear microphone for full size and canalphones.

If it were due to a resonance in the ear-tunnel, you'd find peaks at a fixed frequency and multiples of that frequency, not multiples of the input frequency.

The info on wikipedia is pretty vague. Anyone know how an armature really works?

 

[ilmari]

Compare Sennheiser CX300, Shure E2C and E3C on headroom's graphs. The non-armature CX300 and E2C have distortion peaks too, and check out the frequency where they appear...

 

[jinx20001]

i dont know for certain but if i was going to have an educated guess i would say because armatures are much smaller and very sensitive, and as we all know...generally more accurate than dynamic drivers. This is where the problem occurs, bass tones are more powerful than mids and highs so as such disrupt the mids and highs.

now more to the point what im saying is the armatures increased sensitivity may cause bass to disrupt mids and highs. Dynamics on the other hand are generally less sensitive and therfor do not amplify disruptions in mids and lows.

this ofcourse is a complete guess but i do think its a sensitivity issue and armatures picking up more detail. I could be completely wrong but hey i had a go

 

[jinx20001]

i read my last post back to myself and i really do sound like i have not got a clue, its rather amusing

 

[Roam]

If you want to visualize it, get an old crappy cone speaker which you're not using anymore. Normally it's driven by the voice coil former, to which the voice coil is attached, the former is generally about an inch to several inches in diameter. It provides a large strong structure from which to drive the cone. Now imagine removing the voice coil former and driving the cone with a toothpick. For obvious reasons the toothpick isn't going to be able to control the cone as well, thus more distortion.

Granted, it's not quite that bad with the armature drives used in IEM's, but the same general idea applies.

 

[Claus-DK]

But if the cone is very small the toothpick would be more powerfull and firm than a very small voice coil former.....

 

[Roam]

With a conventional headphone driver, the voice coil & former goes around the entire outer perimeter of the diaphragm. An armature design has a little stick (much smaller than a toothpick) in the middle of the diaphragm, it does not provide an optimum mechanical interface.

 

[vesther]

Most of those IEMs suffer from distortion because they're strictly closed-air, but that could be me and I'll have to read the links to see why for sure.

I was really shocked to know that open-air headphones literally have less distortion than closed-air IEMs. I just can't believe that a UE IEM has more distortion than a Senn.

 

[jesse_w]

In addition to that, armature driver enclosures are built in such a way that the sound must reflect off a surface directly in front of the driver and through the sound tube to exit at a 90 degree angle to where the transducer is facing (this saves space). Armature drivers are generally poor performers and only make sense where space is an issue. (Statements to the contrary are myths generally perpetuated by people who do not own any good full-sized headphones).

There has been alot of discussion on this in the past, particularly to do with the ER-4. if you dig up some old threads you will find in depth discussion and diagrams.

jess

 

[b0dhi]

Quote:

Originally Posted by Roam /img/forum/go_quote.gif With a conventional headphone driver, the voice coil & former goes around the entire outer perimeter of the diaphragm. An armature design has a little stick (much smaller than a toothpick) in the middle of the diaphragm, it does not provide an optimum mechanical interface.

So the harmonics are caused by the rod vibrating? It seems like it would be too rigid to have strong harmonics under 1000hz, wouldnt it?

 

[PiccoloNamek]

Those pictures don't look anything like an actual balanced armature driver. Perhaps this will help:

Quote:

Armature drivers are generally poor performers and only make sense where space is an issue. (Statements to the contrary are myths generally perpetuated by people who do not own any good full-sized headphones).

I'd have to say this is just plain incorrect. Armatures don't sound any worse than full-size headphones, they just don't have some of the same qualities, like impact and bass presence.