One thing I can't get my head around is how the proponents of burn-in are so sure of the changes - when our accurate aural memory (perception of differences over time) seems to be much less than 20 seconds?
For a discussion on it - see this thread from hydrogenaudio (
http://www.hydrogenaudio.org/forums/index.php?showtopic=71595)
I'd be really interested to know if there are any studies that show (for perception of details) how much we can actually retain over time - and reliably differentiate.
The reason I ask is simple - how on earth can anyone tell what the
actual difference is between 2 points of listening several hours apart - if our aural memory for detail only extends reliable for a few seconds.
I have personally found no audible effect of mechanical break-in with any of the headphones I've owned - but then again, I wasn't expecting any. I have found that at first listen - I may find a headphone's sonic signature to be strange (not what I'm used to) - but after a while listening to it (and only it). my wonderful brain adjusts it's expectations - and the sound changes. This is an easy experiment to do - especially for owners of multiple headphones. Take you headphones with the most 'different' sonic signatures. Listen to one for a few hours. Now switch to the second - note immediate reactions - but keep listening to the second (again for as much time - hours - as possible) - then switch back to the first again. Write down your observations.
Switching from HD600 to SR325i to HD600.
- HD600 initially sounds spacious, textured, natural - incredible timbre. No sign of veil. Switch to 325i ......
- 325i sounds narrow, overly bright. harsh even. After some time with it - it sounds energetic, highs are enticing, everything sounds alive and brilliantly clear - not harsh in the slightest. Don't notice the narrow stage as much any more. Bass is tight and accurate and a lot of fun. Switch back to HD600 after 2 hours ......
- HD600 sounds slow, dull, distant. Bass is boomy.
Give it a couple of hours - and then the HD600 returns back to the first bullet point again. I know this is an extreme example - but it highlights the reality of our brain's impact on perceived sonic changes. Have the headphones changed over the 5-6 hours listening ....... no - both my cans would be considered well broken in by now. So how can the change be so 'night and day' ........
Tyll's experiments with the AKG 701s highlight how little measurable mechanical change actually happens. Is there a change - definitely appears to be. Is it going to be night and day - not according to his measurements.
People will believe what they want to believe - but
my position is simple. Any burn-in (mechanical) is going to be so minute that my aural memory would never be able to differentiate it anyway. Therefore perception of change is all in my mind. And I can show this (repeatably) by simply swapping different sonic signatures over time.