I use an Oppo universal player (UDP-205, or the discontinued BDP-105), USB drive for storage, plus Chromecast Audio (Toslink connection to Oppo's DAC) for internet based music. I can connect the Oppo's variable output directly to a McIntosh power amp (e.g., a pair of MC30s), or to an integrated amp, or to a preamp. The Oppo can provide bass management, enabling off-loading of the power-hungry low frequencies from the main amp and speakers. The Oppo will play any digital format I need: Blu-ray audio and video (and nascent UHD discs), DVDs, SACDs, CDs, downloaded hi-res FLAC, etc.
I listen to classical music. I don't copy CDs onto a hard drive because, based on what I've read, manual tagging is a time-consuming PITA for classical music. (Apparently "joining" the movements of a symphony also must be done manually.) SACDs would be a PITA to copy because of DRM. I haven't even investigated copying Blu-ray audio or video. Bottom line, I don't perceive a time savings associated with copying "shiny discs" onto a hard drive. (Of course, hi-res downloads (e.g., HDTracks) are on a hard drive.)
Bottom line, the Oppo UDP-205 allows me to play any digital music format, without requiring me to copy my music collection onto a hard drive. And the UDP-205 has a state-of-the-art high-quality DAC.
It sounds like this may not be what you're looking for - but FWIW, that's how I handle digital music with my vintage amps, including McIntosh.
I hope this helps.
I'll be interested in learning from other members' experience.