How cheap can you go and still be happy with the sound?

Wharfedale Diamond 225 - $300 (more low-end extension) or

Sony SSCS 5 $198 (more airy bigger soundstage)

Fosi v3 w/ 32 volt SMPS - $72

Wiim Pro Plus - $220

Mica Awg 14 speak cable $25

RCA cable - World Best cable Mogami 2964 - $27

Total: $644 plus tax (w/ Wharfedale); $542 plus tax (w/ Sony).

No PC please.

Over the last fifty years each upgrade has represented an improvement over the last. First for my main system, then I added a separate headphone system and upgraded it slowly as well. I guess it would be really hard to go backwards at all. I have put an enormous effort into making them better and better.

I put together a top notch ear monitor setup using existing iphone and Roon streaming software for <$200.

Cost goes up from there for other applications depending mainly on room size and other more subjective considerations. Multiple source devices will also up the cost accordingly.

I  have <$3k invested in my family room system which I suspect is one that most people might be able to live with.

I’ve managed to bring down the cost of my "reference" system by several K in recent years but still way more than any of these.

As cheap.......or as expensive as will satisfy your musical preferences!!!  

Let's not be ridiculous. Good sound has a cost and it should. I don't think there is anything under $10k-$15k that would qualify. Assuming one source.