Headphones

Hey all,

I currently use Meze Lirics with a Chord Mojo 2, source is either Roon on my desktop (all FLACs) or my iphone (FLACs on onkyo app). Its been working for me, but I'm ready to make the step up to 'end-game' open backs as I have more space in a new home now and can set hardware up.

I've recently tried these 4 headphones:1.Focal Utopia2.Meze Elites3.Final D8000 Pro4.DCA ExpanseAnd I'm finding time to trial the LCD-5s and Abyss 1266 Phi TC as well. Of the 4 above, I prefer the D8000s and Expanse- BUT the expanse gave me noticeable jaw ache after about 20mins so I'm on the fence about it.

Even though I haven't tried the Abyss I suspect based on numerous reviews I've read and my genre preferences it may be a top candidate. If not, I'll prob go for the Expanse (if I try again and feel like I could get used to the pressure) followed by the D800s. Genres I listen to are Rock (all sub-genres included), EDM and Rap.

I'm undereducated with regards to the finer details of the different types of amps, DACs and I've never owned a DAP either. Could use some help from you fine folks

Questions:

• Amps - I've shortlisted a number of headphone amps; my understanding is that amps just have to deliver enough power to drive X headphone and any supposed effect on sound quality is a contentious point in the community. True?
• DAC - Wild variety out there and the more I read the more bewildered I get. Is there a DAC type and/or brand out there that suits the 3 genres I like? I need help homing in on a few models
• DAP - Is it possible to skip buying a desktop DAC, and just get a high powered DAP to connect to my amp and thats it? Sidethought here is I could use this DAP for my Meze Lirics at the office as well so I get more utility out of my hardware. If this is possible, which DAPs out there could work for the 1266s / D8000 / Expanse?

Budget: Excluding what I spend on the headphones- US$10-15k max for amp + dac/dap

Would greatly appreciate any advice, thank you folks in advance!