Yeah definitely, I had heard that hd650s paired with a nice amp were about as good as you could get for under 3-4K wasn’t sure if anything made it to market that’s been really revolutionary. Really my problem is music discovery. Spotify doesn’t really do it for me, it just finds more of the same and never invites me to branch out.
I built the nwavguy O2 kit from jdslabs and like it. It does perk up the Sennheisers and would probably work well for your headphones.
I don't hear a lot of difference between the Apple headphone adapter and jdslabs' "Objective DAC". The $10 Apple adapter might even be better than the ODAC, but it only works with my phone.
I haven't used Spotify in years; I think I never reinstalled it when my old laptop died in 2018. I could never get past the audio quality of their free tier, and never tried the paid tier. Maybe it's better now. Their recommendations back then for me were really odd; I can understand why some people would complain. I am about the only person that likes Amazon's streaming service but their recommendations are just bland-to-bad. I've noticed Pandora channels have become much more repetitive. Maybe the whole industry has been pushed by their metrics to some horrible least-common-denominator point.
