nikongod
DIY-ku
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- Jan 24, 2005
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Quote:
Quote:
The amp is cap coupled. there is no normal way to put DC CURRENT into the headphones, so we are safe from the 10-seconds of DC current that some direct coupled amps with SLOW dc servos can give. That settles that.
If you watch the output with no load, I agree it will go HIGH and then settle. Load it down a bit more, it settles down really quickly.
Also, its *only* a 12v spike. I have put 12v (p-p) into hd-580 for a few minutes... I was curious if the Supra would clip audibly at that level. It didnt and actually sounded nice although loud enough to be clearly heard down the hall - the headphones were on my bed, not on my head.
posts elsewhere have commented on Joe (or is it John) Grado breaking in heapdhones with a speaker amp. I guess they can get new heapdhones pretty quick if they need to, but if this technique resulted in destruction too frequently they would stop dont you think?
I am personally more concerned with what the turn-on pops could do to your ears than the headphones. the HD-580 were FAR from safe listening levels in my above example...
Originally Posted by tomb /img/forum/go_quote.gif Um ... with a 25V power supply, you'll see 12.5VDC to Ground at the Left and Right channels, until the output caps charge up. Typically this takes about 5 seconds. That amount of voltage is enough to kill headphones, I think. The admonition has always been: Don't plug in your headphones until the thing has warmed up for at least 10 seconds. Same for turn off - get the headphones unplugged before you turn it off or they'll see killer offset. |
Quote:
Originally Posted by n_maher /img/forum/go_quote.gif Has anyone ever actually had headphones damaged this way? I've had continuous exposure to DC offset nuke a set before, but I've used my Millett for a good long time and never had it hurt a pair of phones when I left them plugged in. |
The amp is cap coupled. there is no normal way to put DC CURRENT into the headphones, so we are safe from the 10-seconds of DC current that some direct coupled amps with SLOW dc servos can give. That settles that.
If you watch the output with no load, I agree it will go HIGH and then settle. Load it down a bit more, it settles down really quickly.
Also, its *only* a 12v spike. I have put 12v (p-p) into hd-580 for a few minutes... I was curious if the Supra would clip audibly at that level. It didnt and actually sounded nice although loud enough to be clearly heard down the hall - the headphones were on my bed, not on my head.
posts elsewhere have commented on Joe (or is it John) Grado breaking in heapdhones with a speaker amp. I guess they can get new heapdhones pretty quick if they need to, but if this technique resulted in destruction too frequently they would stop dont you think?
I am personally more concerned with what the turn-on pops could do to your ears than the headphones. the HD-580 were FAR from safe listening levels in my above example...