[MDR30]

Quote:

I know with the Fischer FA-003/Brainwavz HM5, the pads are quite stiff. Over time (with lots of use) they become softer, and bring the drivers closer to your ears.

These are headphones that are said to "greatly benefit from burn-in". 

 
 
This is a very astute observation. The pads play a tremendously important part in the final perception of sound quality, especially in planar and closed type headphones. It may often change through a listening session, when the pads warm up from body heat, and evaporation, making a seal to the ear and also the pad foam adapting to the shape of the ear.

 

[Currawong]

Pads softening will do it for sure. 
 
I have some un-used Symphones Magnums drivers I've kindly asked Tyll if he can test over a few days, since I'd swear the level of bass changes over the first few dozen hours of use and I have multiple pairs here. I don't know if Rhydon runs them in, I need to ask him. I'd guess during QC manufacturers would have to put a few hours on drivers, depending on how expensive the headphones are.