Opinions please on a starter audiophile system?

I am in the process of completely revamping a long standing 2 channel stereo system consisting of older Polks, big box store sony cd / amp.
I suppose I could classified as a "newbie" to audiophile components but believe I can drastically upgrade with a desired budget of $4K.
Would love to hear opinions and thoughts on amp/cd/speaker components that fit that budget.
Have researched much, auditioned little, though trying to finally go hear, make a choice and get off the audio merry goround.
Musically we listen to a variety of stuff - jazz, folk, rock, jambands, lots of archive.org stuff. Logistically, the system will reside in the living room 14x 18 of a 9 foot ceiling'd post and beam house with open floor plan. HELP? Much thanks.