[Lopson]

Hey guys, I'm having a really annoying problem with my Sennheiser HD600. A few weeks ago, I took it apart to clean it. Ever since then, the audio's been uneven. What I mean by that is that the sound coming from the right channel is noticeably more powerful than what's coming from the left. Do you guys know of a reason why this might be happening? Here're some more details:
 
- When I took it apart, I substituted the foam (not the ear pads!) inside both earphones. They're both made out of the same material and have the same thickness;
- While cleaning them, I touched the membranes of the speakers with my (gasp!) bare fingers ever so lightly;
- I'm not using any sort of phone amplifier. I'm connecting them directly to my computer's integrated sound card (woe is me);
- I've tried plugging them to various devices which don't really have the juice to power them up properly, and in all of them, they sound uneven.

 

[Slaughter]

It doesn't sound like you did anything to damage them. Try unplugging the cables from the cups and reattach. Check your entire cable for any damage.

 

[Lopson]

Quote:

It doesn't sound like you did anything to damage them. Try unplugging the cables from the cups and reattach. Check your entire cable for any damage.

 
The cable seems to be in good shape. Plugging and unplugging the cable seems to do nothing. Everything inside is properly fit.
 
The thing that gets me is that it's a very small difference. So small, in fact, that is making me wonder whether or not it's just my mind and my ears playing tricks on me. Is there a way for me to measure the volume output of each channel? It's really driving me up the walls!

 

[Slaughter]

Two things you can check.
First, get a multimeter, set it to ohms, place one probe on the largest ring on the plug, closest to the cable (ground), put the other probe on one of the two other rings on the plug. Do this for the other ring. This will give the resistance in ohms of each driver. The two readings should be very close.
Next, get an SPL meter, make a cardboard cutout the same shape as your pads with a hole in the center, the size of the end of the SPL meter. Play some pink noise, place the cutout over the pad, insert the spl meter (set to C weighting) and measure the loudness. Do the same for the other driver. Readings should be the same.

 

[Moonwalker]

Hi!
 
Try removing rear grilles and push the drivers until they click back into place. One of them could be loose, causing this imbalance.
 
Moonwalker
 

 

[Lopson]

I don't have all of the materials to try all of that, Slaughter, so I'll first go with Moonwalker's idea. Thanks for all the help, guys, your suggestions and knowledge are priceless!