Originally Posted by vinjeman
Burn in is for the type A's out there (alot of them on this thread). Imagine going to Best Buy/Magnolia and asking the salesperson "how long have these cans been burned in?" Please, some engineer explain to me what burning in a set of anything (other then perhaps tubes) will have an audible effect? Can you see Monster running an ad that reads "our superior cables are pre-burned in for your audio satisfaction"!!
note: If marketing takes this and runs with it I want a percentage!
trust only your ears...
[tripping as I step off the box]
There's a statement behind all burn in types, the question is how big of an effect does it have? When you burn in a pair of headphones (while not using them on your head) you do send current and run quite a few things: the cabling as well as the drivers. The drivers themselves are moving parts that will become less rigid and move a little mores smoothly after they've been moving for a little while. In many ways, it's like a pair of shoes, they become more flexible, and less rigid, with time and use. This has been shown in measurements already, Tyll has found that if you do burn in a pair of headphones, distortion reduces.
The other main thing that is run is the cabling. If they aren't silver cables, copper is known to go through oxidation. When it oxidizes, it takes conductive copper and turns it into non-conductive copper-oxide. This can be seen on clear IEM cables easily (they turn green). Additionally, it mainly oxidizes around the exterior of the copper (not internally). This would reduce the cross-sectional area of the cabling and will impact the resistance the cable offers by reducing it (smaller cross-sectional, conductive area => more resistance). Any change in sound would rely on the impedance curve of the driver assuming the resistance change is large enough.
The above is what will happen to the components when you burn them in. Whether or not it will be audible is questionable. That is a question of intensity rather than just the fact that it happened. Also to note, unless monster is burning in their analog cables, there is no reason to burn it in. HDMI cables use digital transmission, it actually won't matter if the cable is burned in or not as digital only transfers bits rather than bits, amplitude, and frequency (what analog does).