[Shinsengumi]

I have a problem with my relatively new AKG K701. I've used them for over a month.

Equipment:

Marantz CD5003 --- Cambridge DacMagic --- Little Dot MKIII --- AKG K701

Problem:

Now and then I experiences a hissing noise sound or crackling on bass notes. I feel that it is most prominent heavy bass music. Noise occurs only in the right earpiece. The noise are significantly audible if you put your ear against the outside of the earpiece. It is not a constant noise but the noise is, when it occurs, as I said, on bass notes.

The strange thing is that I can listen for hours with great sound quality for several days. Then, suddenly, the noise will appear. It always comes after I have listened for at least half an hour at a stretch.

Tried:

I've tried without DacMagic, only with the CD, just the computer, but the noise is there. When I tried another headphone, a significantly poorer (Canman HP-660), the noise is gone. On one occasion when I switched from HP-660 to K701 the noise disappeared from the K701. Loose connection? When the sound occurs, I nowadays usually try changing back and forth, eased a bit on the plug, but it doesn't work anymore.

I'll try:

Clean the connector on the headphone amplifier. Which way is the best?

What do you think? Is it wrong on the headphones? Loose connection? Dirt in the connector? Faulty headphone amplifier?

 

[fjrabon]

for heavy bass notes, the driver has to flex farther, maybe it's hitting some hair or something that it doesn't otherwise touch when it doesn't have to flex as far.

 

[Shinsengumi]

Quote:

Originally Posted by fjrabon /img/forum/go_quote.gif for heavy bass notes, the driver has to flex farther, maybe it's hitting some hair or something that it doesn't otherwise touch when it doesn't have to flex as far.

I am almost bold, so I don't think it is a possibility. And it is weird that it happens randomly and only on the right earphone. But I am grateful that you took your time to answer!

 

[fjrabon]

Quote:

Originally Posted by Shinsengumi /img/forum/go_quote.gif I am almost bold, so I don't think it is possibility. And it is weird that it happens randomly and only on the right earphone. But I am grateful that you took your time to answer!

you'd be surprised where hairs can come from. Could have been in the driver from the factory and finally just worked it's way into contact with the driver.

My main point was that it seems you have done a good job of isolating it to the headphone, and a specific side at that. Which means the most likely culprit is either something is in contact with the driver, or something is otherwise going on with the driver.

 

[Shinsengumi]

Quote:

Originally Posted by fjrabon /img/forum/go_quote.gif you'd be surprised where hairs can come from. Could have been in the driver from the factory and finally just worked it's way into contact with the driver. My main point was that it seems you have done a good job of isolating it to the headphone, and a specific side at that. Which means the most likely culprit is either something is in contact with the driver, or something is otherwise going on with the driver.

If you are right what can I do to get rid of the problem? I took a quick look and it doesn't seem to be easy to look at the driver.

If my problem is the headphone, it would be the easiest, because then I can return them to the shop. I just want to make sure that the headphones are the problem.

 

[warrior05]

I'm going to agree with fjrabon that you've got something foreign on the driver. It might be a hair or it could be something else. I once had a tiny drop of glue break off and lay on the driver. The bass notes are when the driver is moving most and usually when you will hear if something is on it.

One thing you can try is take off the pad and foam so the driver is exposed. Gently blow on the driver from as sharp of an angle as you can from various angles. Don't blow too hard. Doesn't take much if it is a hair.

 

[Shinsengumi]

Quote:

Originally Posted by warrior05 /img/forum/go_quote.gif I'm going to agree with fjrabon that you've got something foreign on the driver. It might be a hair or it could be something else. I once had a tiny drop of glue break off and lay on the driver. The bass notes are when the driver is moving most and usually when you will hear if something is on it. One thing you can try is take off the pad and foam so the driver is exposed. Gently blow on the driver from as sharp of an angle as you can from various angles. Don't blow too hard. Doesn't take much if it is a hair.

I took off the pad and looked at the driver. I couldn't see any foreign material like hair or glue, but I made a gentle blow and assembled everything. After half an hour the noise occurred again. Frustrating!

What is my next step?

 

[cavedave]

Is the amp a tube amp?
I had the same thing happening with my MG head only in one chanel every once in a while tried changing interconnects all kinda stuff. Then i changed the signal tube have not had the same thing happen. And the tube was suppose to be new
i figure one of the sections was bad. Something to think about if you have a tube amp and said problem.

 

[Shinsengumi]

Quote:

Originally Posted by cavedave /img/forum/go_quote.gif Is the amp a tube amp? I had the same thing happening with my MG head only in one chanel every once in a while tried changing interconnects all kinda stuff. Then i changed the signal tube have not had the same thing happen. And the tube was suppose to be new i figure one of the sections was bad. Something to think about if you have a tube amp and said problem.

Yes, it is a tube amplifier. But I have the same problem when I am using the internal amplifier in the Marantz CD5003.

Is it a possibility that some foreign material have gotten in through the outside and in through the grill?

 

[warrior05]

It isn't surprising you didn't see anything on the driver. It can be something pretty fine and light colored. So you had success for a half hour. There is a chance you just moved whatever was on the driver to another spot on the driver and now it has worked its way back so it is making the noise. I think it is worth another shot. If still no dice, then I say contact AKG and let them deal with it especially since they are new. I wouldn't tell them about your attempts to fix it but definitely tell them that the symptom happens with multiple sources/amps so they know it is the headphone and not your equipment.