I have an old (1990s) Aura VA100 amp and B&W speakers of similar vintage, both second-hand. I used to have a more expensive amp but wasn’t convinced I could hear a difference and I like B&W’s industrial design.That seems like something I‘d be interested in. What‘s your amp?
I use a Chromecast Audio to stream Spotify and BBC Sounds app to my HiFi as well, but if you just want to play your own files then you can do it without streaming hardware as I’ve described.
Khadas Tone Board was reviewed on ASR; it’s not perfect, but as far as I understand from Amir’s review, it’s imperfections might not be audible. I put mine in an ABS project box costing about £5. There are countless transparent DACs costing not much more than the KTB, and others on ASR could advise whether you are likely to hear a difference.
There has been discussion on ASR about whether Audirvana is bit perfect or not, but the remote app works smoothly and has a pleasing user interface in my view. After years of struggling with JRiver it was a relief to find something relatively simple that just works.
I hope this helps.