[DeadBoys]

Hi all,

Recently I have noticed that the right driver of my headphones (HD650, K701) have been producing far more bass that the left hand driver. It started off barely noticable but has gotten, it seems, progressivly worse.

I have only noticed the problem after a recent DAC acquisition and, suspecting this might have something to do with it, stuck the probes of my meter (Fluke 177) into the 2 "fixed out" RCA sockets. Sure enough the DC offset of the left channel was some 16mV. I checked the right channel too and the offset was more or less 0V (around 0.2mV).

The DAC feeds my M^3 which I have used in conjunction with my Essense STX for over a year without problems.

So I guess question that I'm asking is:
Is 16mVDC offset, fed into a M^3, enough to cause this kind of problem in headphones over a relativly small period of time (~2 weeks)?

Also, it seems that the imbalance is now perminant, as trying the headphones in question on my iPod still reveals a small imbalance.

Hoping for anyone who has an insight into this kind of matter to give a quick opinion, that'd be great.

Thanks

Leo

 

 

[ford2]

 
 
Why not test the DC offset at the amp,that is where it matters.
 
As a general rule anything under 20mV is fine although the lower the better.
 

 

[DeadBoys]

I have been speaking to Jan via PM and he has suggested that it may be due to me having a cold as this would explain why both my K701s and HD650s show signs of the imbalance. I hope it is!

By the way, Jan is honestly one of the nicest guys I have ever had the pleasure of speaking too!

Thanks too for your suggestion ford2, if the imbalance is still around when the cold goes I will look into it for sure.

 

[cyberspyder]

Clean your ears? My only advice.

 

[DeadBoys]

Thanks for the advice cyberspyder.
I have already been to the doctors and they said there wasn't really any wax in there at all. (Note this was after I posted this thread)

 

[Christopher]

I have a similar problem with my 650s - I drive them directly from various portable or fixed sources (no separate headphone amp or anything like that, I'm far too poor to afford fancy things.) I've noticed for a while now my cans have begun to exhibit an imbalance - the R channel appears to be one to two or three decibels louder which is absolutely infuriating. I've fired off an out of warranty enquiry to Senny UK and I'm wondering if they could fix it for their flat £34 fee (hopefully so!)
 
I often leave my cans plugged into the output of my PC's audio interface (which is usually outputting silence, however it's still of course supplying voltage down the cable to the cans). My cheapo multimeter shows each channel (by touching the poles on the plug that goes into the headphones) having 82.5ohms of resistance and supplying an even 0.03v per channel.
 
Will having cans driven even by this miniscule amount of idle voltage with no 'sound' from my PC negatively affect driver performance over time? I've tended to just leave them plugged in out of convenience to date (my audio interface is round the back of my PC and I hardly ever take the cans elsewhere except when travelling).