I only download music anymore, which is almost exclusively from
Bandcamp. That's because they make music available in high-resolution formats like FLAC and WAV. I don't buy music if it's only available in mp3, and I avoid iTunes (because the last time I tried using their software it began to rearrange my stored music catalog in ways I did not appreciate).
The DAC I use has better sound-reproduction capability than my desktop or my phone, because that's all it was designed to do.
Oh, and I'm almost sixty years of age
edit (because I forgot the title of the thread): The DAC I use is made by FiiO, and is the
M9 model. I bought it at the beginning of last year to replace my slowly failing Cowon Z2 DAP (digital audio player). Before that, I had a Cowon S9. Neither of those models are made anymore.
For headphones, I now use a pair of Hifi-Boy Dream earbuds, 32 ohm. Previously, I had used a pair of Yuin PK3s. Big headphones are just too heavy for me, and I hate having my ears pressed against my head (having used such headphones for years in public radio). IEMs might be okay, but I haven't spent the money to determine if I'd like them or not. There is a pair of Denon IEMs that had a good review, even for the foam cushions, but they were pricier than the earbuds I bought instead. And they were still about two-thirds the cost of the Denon set.