[daltonlanny]

Something mysterious has happened, and I cannot figure out why.
Does any one out there have any answers, or had it to happen to them?
As you may know I received a brand new pair of Beyerdynamic DT880/600 ohm headphones on Tuesday.
As soon as I received them, I made sure they worked and I tested the impedance.
Fresh out of the box, the impedance measured 605 ohms in the left channel and 597 ohms in the right channel.
I have had them hooked up to my Headroom Micro Amp, with my cd player hooked to the Micro Amp, and a cd playing pink noise through them for the last two days.
Out of curiousity, I unhooked the 880's from the Micro Amp and measured the impedance again a few minutes ago. I was shocked. The left channel now measured 572 ohms and the right was 580!
Thats a 25 ohm drop!
What would possibly cause this, and is it normal?
Are my 880's defective?
Will this negatively affect the sound?
Any help or answers would be greatly appreciated.
I also sent an email to Beyerdynamic to see what they have to say about this drop.
 
LD

 

[daltonlanny]

Anyone?
This has me sort of concerned.

 

[MDR30]

A normal multimeter can only measure resistance (DC), not impedance (AC).
 
The change you notice is of no significance.
 

 

[wasp131]

I noticed similar differences with my dt990/600's a few months back.
Dosent appear to cause any problems to me.
stop worrying and enjoy them

.

 

[MacedonianHero]

Check this out:
 
http://en.wikipedia.org/wiki/Gage_R%26R
 
errors in a measurement system: variability of the part, suitability of the gage, and errors introduced by the person taking the measurement.