Hi
having got back into music via Hi res flac format I'm on the lookout for recommendations regarding a headphone upgrade.

Current set up is Astell & Kern ak70 mk11 with some Sennheiser on ear Momentum headphones, looking at the same make again I've come accross hd 600 which are highly regarded but also hd 800 and hd 800s, the latter are 3 times the price of the hd 600, so is the asking price worth it ?

Also are there other makes worth tracking down for a listen ?

impact,timing and sound staging are what I like in music