[grave architect]

Hey guys,
 
I recently got a pair of the AKG k271 mkii's and the pa2v2 amp.  Problem is, recently I was listening to Pet Sounds (with the amp) and during certain points (like, say, the heaviest/bassiest/most booming parts of Let's Go Away for a While), the right can will buzz/crackle pretty noticeably.  It happens at other points in the album as well -- it seems to be at bass heavy points in the song.  I thought it was just an issue, possibly, with the Pet Sounds album file or something, but this morning I was listening to Daydream Nation and noticed it very prominently again during most of Teenage Riot, as well as with other tracks on the album.  I'm trying to figure out exactly what triggers it, but I'm not completely certain. Any ideas, or experience with this from anyone here?  It almost sounds like a car speaker that has blown, at least slightly. It's unsettling and really bothering me. Is it possible that I'm trying to listen too loud?  I figured the headphones/amp were powerful enough to handle the volume, and it's not like I'm listening at insane levels.
 
I've also read about strands of hair getting stuck and causing problems -- could this be the cause? For the record, I am using my iPod touch with the amp.  Any thoughts/assistance would be greatly appreciated.  Thanks a lot.

 

[K_19]

The hair/dust issue is worth looking into. I had a bass buzz/rattle issue on bass with my MA900 and sure enough, there was a hair in there somewhere. Grados also have their famous "grattle" problem where a caught hair is often the culprit. Remove the K271 earpads and have a look, perhaps gently blow around the drivers with your breath or canned air and see if it helps.
 
Otherwise, it could be the problem with the headphones themselves... AKG's for whatever reason seem prone to this... K7XX bass rattle issues have been well documented and I also had a K701 in the past which developed a bass rattle.

 

[grave architect]

Thanks for the quick response (and sorry for mine being delayed -- busy weekend).  I might have found the issue, but maybe you can help confirm... So I've been using the pa2v2 amp with the k271's on the train to and from work.  I do like to listen fairly loud, but I don't imagine it's a volume that is out of the ordinary with other headphone listeners trying to soak in all the sounds that can be captured with good headphones.  I think the buzz/crackle/blown-like sound is simply me upping the volume too much -- I do have my ipod volume about all the way up, and the amp volume knob almost all the way as well.  The strange thing is, one would expect the volume to be ridiculous with these settings, but it really is just about right.  The only unfortunate part is when the crackle comes in.
 
So i decided to do some testing. At home, I got out my Schiit Magni amplifier and tested both my k271's and my HE-400's using the songs that I've encountered this problem with.  Well, with a more powerful amp, the k271's hooked up through the Magni didn't produce the crackle.  I then tried the HE-400's through the pa2v2, and had the crackle issue.  My conclusion would be that the pa2v2 just isn't powerful enough to drive as loud as I would like.  But for what it is -- a pretty great portable amp -- I guess I can't complain.
 
I am curious; does this check out to you more experienced headphone/amp users?  Am I just pumping the volume a little too high for the pa2v2 to handle without crackling here and there? Or should that not be happening?
 
Thanks guys.