[ericj]

Quote:

I put up a flyspray http://www.rockbox.org/tracker/task/11812 and saratoga has taken notice. He mentioned fade to pause which in theory would zero it on pause but I checked and I had it on.  I tested it and it doesn't make a difference either way so I'm not really sure what the cause is now. But I did find I get a squeak at pause and unpause with fade on but not with it off, the squeak is what led me to measure the DC offset in the first place

 
saratoga is a sharp guy. Good luck. Perhaps sunday or monday i can try this out with some other AMS based devices.
 
 
wrt the other - I know that caps don't block transients, but the way the behavior was described made it sound like constant DC.
 

 

[porthillsbomber]

That would be good as another guy on the rockbox forum has said he gets the little squeak which I think is an associated problem on his Fuze.



 
Quote:

Good luck. Perhaps sunday or monday i can try this out with some other AMS based devices.
 
 
 

 

 

[Ogham]

I am currently experiencing that horrible sinking feeling..
 
I'm using a Clip+ and a new pair of Sennheiser IE-8's (16-Ohm), I run rockbox with fade to pause enabled and often hear the pause/unpause squeak.
 
Is it possible that I have already damaged these IEM's? How much might I have damaged them?

 

[porthillsbomber]

I think it is unlikely that you will of damaged them as the DC isn't during the music (well I'm still using my clip+ anyway) but the problem hasn't been solved as far as I know.
 
Quote:

I am currently experiencing that horrible sinking feeling..
 
I'm using a Clip+ and a new pair of Sennheiser IE-8's (16-Ohm), I run rockbox with fade to pause enabled and often hear the pause/unpause squeak.
 
Is it possible that I have already damaged these IEM's? How much might I have damaged them?

 

[Ogham]

Thanks for that, it is a welcome relief! I'm glad you seem happy to continue using rockbox on your clip+!
 
I know very little about this sort of thing - which makes me very tempted to switch back to OF for peace of mind.  Do you think that is an overreaction?
 
Quote:

I think it is unlikely that you will of damaged them as the DC isn't during the music (well I'm still using my clip+ anyway) but the problem hasn't been solved as far as I know.

 

[Ogham]

porthillsbomber,
 
Is the following statement on the Flyspray bug report still valid?
 
Quote:

This has a real potential to damage headphones if you have the volume up and were unlucky enough to pause on a peak.

 

[porthillsbomber]

Na I thought about it some more and I don't think so unless the DC impeadance of your phones is very low and the coil over heated as a consequence.
 
Edit: Well, that was the question I was asking when I started this thread so I'm not entirely sure but I'm pretty sure the answer is no.

 

[Ogham]

Would 16 Ohm Sennheiser IE-8's be considered 'very low' in this particular situation?
 
Thanks again for shining some light on this for me, I've been worrying about it all night!
 
Quote:

Na I thought about it some more and I don't think so unless the DC impeadance of your phones is very low and the coil over heated as a consequence.
 
Edit: Well, that was the question I was asking when I started this thread so I'm not entirely sure but I'm pretty sure the answer is no.

 

[porthillsbomber]

Na I guess I mean very low compared to it's nominal impedance as that is what will set the volume you have your clip+ set at. I mean if it can handle that sort of fluctuating voltage while listening to music it should be able to handle it as DC. The only occasion I can see that you would get in to trouble is if you had been listening to high impedance/ low efficiency cans through with an amp and then you paused and plugged you IE8s back in to the amp. Until you turned down the volume you could have something like 5+VDC in this case which I would guess a pair of IE8s wouldn't like.

 

[Ogham]

Cheers porthillsbomber, that gives me a lot more confidence to continue using rockbox! (My IE-8's have been in 'stasis' since finding this thread).
 
So basically, you don't see any risk of coil overheat or mechanical diaphragm/membrane damage due to the 200+ mV DC with 16 Ohm impedance?
No more questions I promise! I appreciate you taking the time to answer me very much!

 
Quote:

Na I guess I mean very low compared to it's nominal impedance as that is what will set the volume you have your clip+ set at. I mean if it can handle that sort of fluctuating voltage while listening to music it should be able to handle it as DC. The only occasion I can see that you would get in to trouble is if you had been listening to high impedance/ low efficiency cans through with an amp and then you paused and plugged you IE8s back in to the amp. Until you turned down the volume you could have something like 5+VDC in this case which I would guess a pair of IE8s wouldn't like.

 

[porthillsbomber]

No, I don't think so. You would never get that much anyway because I measured that with the volume at max.

 

[Ogham]

Many thanks porthillsbomber

 
Quote:

No, I don't think so. You would never get that much anyway because I measured that with the volume at max.