I consider the A900 to not be portable in the slightest. It is a straight up home and office can. Also, they don't seem like the most durable headphones - definitely not for backpacks, assuming you could even fit it into one. 
Also, they are very, very awkward if you try and wear them around your neck. You can't move your head hardly at all.

Also, they are very, very awkward if you try and wear them around your neck. You can't move your head hardly at all.






