Do headphones requiere break-in?

Absolutly Yes. Good rule of thumb is 100-300 hours. Depending in the phones. Don't just leave them on 24/7. Give them a break every 4-6 hours.

Yeah they do, usually about a minimum of 20 hours playing nonstop at least. But there are a lot better phones out there if you have money, from $700 for the Hifiman HE500 (awesome to me and a bargain) to the $2000 Fostex TH900. It sounds like both of these would suit your taste. Check out head-fi (with a great thread on 50 flagships compared).

Hi Dmacg

I'm curious. Why the pause every 4-6 hours on headphone break-in? Also does the volume matter? The reason I ask is that during the off hours when I'm not listening I play white noise at a pretty high level on my headphones to break them in. Then when I do listen I turn it down and play at a normal level.

My HD650 and AKG 702 sounded great from the first day til this day. My Grado SR60 sounded bad from the first day until this day. They are not very good. And they are uncomfortable also. Another high-end legend. Same category as the Sony 5400 entry level Vandys and the Oppo stuff. Does not mean they are all bad, just over hyped. Anointed 'Giant Killers'.

Hi Jedinite24;

A few years back in conversation with John Grado about breaking in headphones his suggestion was to use music (choosing something with good dynamic range and across the spectrum from lows to highs), give them a break every 4-6 hours and set the volume a bit higher than your normal high ideal listening level. To be honest, I didn't have the gumption to ask him to explain the whys and wherefors, just thought he knows what he's talking about.
Cheers; dmacg