[Jupiterknight]

Is the rattle somehow related to serial # and if so, what is the pattern and how loud do I have to turn my amp up and at the same time not be assured of that my amplifier isn't clipping.
Does the volume increase have to hurt my ears before the rattling sets in? 

 

[earthpeople]

I got serial number 000093 and I have rattle on the right side. Only happens at very low frequencies and at volumes I would never listen at, so I might not bother sending them in. I have sent an email into support so I guess I'll mull it over while I wait for a reply. 

 

[sonic2911]

  I got serial number 000093 and I have rattle on the right side. Only happens at very low frequencies and at volumes I would never listen at, so I might not bother sending them in. I have sent an email into support so I guess I'll mull it over while I wait for a reply. 

what song do you hear the rattle clearly?

 

[earthpeople]

That's the thing -- the required volume is far too loud for me to listen to without getting a headache and even turning it up quite loud on some songs with deep bass, I can't pick it out. It's easy to tell with test tones but real music doesn't go low enough (nor have enough volume at those low frequencies) to cause the rattle even when turned up. Maybe I'm a little bit luckier than the others and my problem is just less pronounced. 
 
I probably will send them back since they certainly shouldn't have a rattle at all, even if it doesn't infringe on my enjoyment. Either way, I have a few days until Massdrop responds and maybe I will find a song or something where the rattle does detract from the experience. 

 

[sonic2911]

  That's the thing -- the required volume is far too loud for me to listen to without getting a headache and even turning it up quite loud on some songs with deep bass, I can't pick it out. It's easy to tell with test tones but real music doesn't go low enough (nor have enough volume at those low frequencies) to cause the rattle even when turned up. Maybe I'm a little bit luckier than the others and my problem is just less pronounced. 
 
I probably will send them back since they certainly shouldn't have a rattle at all, even if it doesn't infringe on my enjoyment. Either way, I have a few days until Massdrop responds and maybe I will find a song or something where the rattle does detract from the experience. 

You buy the headphone to listen to the music, not the test tone bro ) anyway if there is rattle, so try to contact AKG.

 

[Stereodude]

I have an obvious buzzing sound in my left ear with my K7XX's when playing test tones at sane volumes.  The right side is fine.  It sounds like the driver is hitting something.

 

[Trae]

I think you guys are over-reacting with this rattle issue. The drivers AKG uses for their k/q7xx (whole lineup) are extremely susceptible to cone breakup and distortion when playing low frequencies loudly, moreso than the majority of the headphones out there. If you look at the diaphragm membrane, you see no reinforcement (compare1 compare2) to make the membrane more rigid for the sake of reducing cone brakeup, and that's why you get the rattling/mechanical distortion. The fact that some of you only hear it when you turn up the volume sets it in stone for me. These aren't bassy headphones at all (whole lineup), despite what some people say about them (mainly referring to that ~3dB bass increase) and they never will be, nor were they designed to be.
 
To test this, play a song where you hear the rattle and physically look at the driver. If you see the outer area of the driver bending, denting, and flexing, then you're witnessing cone breakup. It's normal for these particular drivers because they're not designed for putting out bass that loudly (relatively speaking for this driver, audio technica's 53mm drivers can go MUCH higher without distortion). The same happens to the K712 I had in the past, and the same happens to my pair of K7XXs.
 
Also, AKG's headphones aren't the only headphones to have this distortion. It happens to every headphone. You give it enough power, and something will happen eventually, especially with these headphones because the drivers are really delicate.
 
Anyway, going off of memory, the K712 and KXX sound almost identical. The only difference, it seems, is the earpads. The K712 I had (this was a couple months ago) had the angled earpads, whereas the K7XX pads more closely resemble the non-angled K612 pads.

 

[Oktyabr]

  I think you guys are over-reacting with this rattle issue. The drivers AKG uses for their k/q7xx (whole lineup) are extremely susceptible to cone breakup and distortion when playing low frequencies loudly, moreso than the majority of the headphones out there. If you look at the diaphragm membrane, you see no reinforcement (compare1 compare2) to make the membrane more rigid for the sake of reducing cone brakeup, and that's why you get the rattling/mechanical distortion. The fact that some of you only hear it when you turn up the volume sets it in stone for me. These aren't bassy headphones at all (whole lineup), despite what some people say about them (mainly referring to that ~3dB bass increase) and they never will be, nor were they designed to be.
 
To test this, play a song where you hear the rattle and physically look at the driver. If you see the outer area of the driver bending, denting, and flexing, then you're witnessing cone breakup. It's normal for these particular drivers because they're not designed for putting out bass that loudly (relatively speaking for this driver, audio technica's 53mm drivers can go MUCH higher without distortion). The same happens to the K712 I had in the past, and the same happens to my pair of K7XXs.
 
Also, AKG's headphones aren't the only headphones to have this distortion. It happens to every headphone. You give it enough power, and something will happen eventually, especially with these headphones because the drivers are really delicate.
 
Anyway, going off of memory, the K712 and KXX sound almost identical. The only difference, it seems, is the earpads. The K712 I had (this was a couple months ago) had the angled earpads, whereas the K7XX pads more closely resemble the non-angled K612 pads.

Good guess but I would point out that if it were something as simple as driving them to cone breakup then everyone using the same tests would experience the same thing, or at least higher than the reported 1% of the drop.  The K7xyz are not "bass head" cans but they do VERY well with tight, deep, realistic bass just the same.  Even at way above "normal" listening levels.

This is a QC issue.

 

[Eee Pee]

Pretty easy to open em up.
 
http://www.head-fi.org/t/483861/guide-balanced-akg-k702-with-detachable-4-pin-mini-xlr-cable
 
http://www.headphone.com/blogs/news/13776749-world-s-best-headphone-review-akg-k701

 

[rudyae86]

Sigh. All this rattling makes me want to check out my K7XX but Im too buzzed and stuff to even open the box....bleehh

 

[project86]

I just blasted mine with loud bass-heavy music, far louder than I could tolerate for more than a few seconds, and heard no rattle. Too lazy to break out the sine sweeps and test tones but I'm calling it a non issue on my set.

Sounding pretty terrific off the headphone out of the new Parasound Zdac v2. Output impedance is 10 ohms so in theory not quite an ideal match, but whatever..... It sounds great to my ears.

 

[kid vic]

It doesn't make sense to complain about build quality of a headphone designed for listening to music when it only shows problems outside of what it was designed for; it seems these issues are only found when you play frequencies too loud that normally dont appear in music. This is why warranties only cover manufacturing errors and not misuse or normal wear and tear.

 

[marts30]

Won't be doing these silly freq tests when I get mine...

 

[mangan]

With this test my Creative rattles too,but never appears during musik listening

 

[karmazynowy]

  I think you guys are over-reacting with this rattle issue. The drivers AKG uses for their k/q7xx (whole lineup) are extremely susceptible to cone breakup and distortion when playing low frequencies loudly, moreso than the majority of the headphones out there. If you look at the diaphragm membrane, you see no reinforcement (compare1 compare2) to make the membrane more rigid for the sake of reducing cone brakeup, and that's why you get the rattling/mechanical distortion. The fact that some of you only hear it when you turn up the volume sets it in stone for me. These aren't bassy headphones at all (whole lineup), despite what some people say about them (mainly referring to that ~3dB bass increase) and they never will be, nor were they designed to be.

 
I cant agree with you. It dosn't matter that hp are bassy or not. That kind of dissortion is not acceptable.
 
On normal listening volume level, on this track
 
http://youtu.be/cQHTcJYJRgQ
 
right driver in my K7XX its just like "trytytytytyytyt". Thats not OK.
 
On K550 everything is fine, just clear, deep bass. Is K550 a bassy headphone?
 
 

  Won't be doing these silly freq tests when I get mine...

 
You should.