not read all the posts so sorry if i'm repeating stuff.
pre-conditions.
first we must assume that music reproduction performance is most important, more important than how things look, or seeing out a window, or other living priorities. we are all not able to approach things in that way, and everyone has their own personal needs, but this part is where you start. it's to consider pre-conditions and limitations. what can't change? outside noise sources intruding? noise from system a problem? can these things be addressed?
assuming nothing is off limits, then.......
media---already have? need to acquire? streaming only? this is a separate subject.
non-negotiables;
1. speaker <-> room relationship. can the speaker control the room reasonably? will it overdrive the room when pushed? the music needs room to breathe and expand appropriately for the speaker potential. if you just get this part right you are a long way toward musical satisfaction. miss this part and you will battle every inch, and the music will never be natural and have ease. speaker location and fine-tuning is part of this step.
2. amp needs to (1) be able to properly command the speakers, (2) have a reasonably natural tonal synergy with the speakers, and (3) get fed sufficient juice from the power grid without limiting dynamics.
get #1 and #2 right, and you can plug almost any source into the amps and you are going to be pretty happy. that was the heavy lifting. from here it's all down hill. or forget #1 and #2 and even the pre-conditions and buy headphones.
next there are 2 paths;
A--only one source----beginning level---and it's digital. if restricted budget then forget the preamp or maybe use an integrated amplifier. a preamp below a certain price point will actually get in the way of the best sound. hard to predict where that price point is but mostly you can find a digital source with a volume control. find a streaming source and you are good to go.
B--multiple sources or very high performance direction.
3. sources---too many directions to define. obviously find the best source you can. preamp is still optional but at the top of the food chain a make or break proposition. below that all things are possible.
4. power grid very important.
5. room treatments. re-visit speaker location and set-up. listening position experimentation.
6. signal cables and power cables.
7. racks, resonance control.
8. spooky stuff.
don't forget to have fun and if it's not fun why do it?
system building thoughts.
there is a dynamic process involved in finding the nuance and flow of the music from the reproduction chain. it's seldom linear......since changes can upset the balance in more than one place. and to get somewhere you need to have a target sort of sound you are referencing while making changes. it can be live music, but that is not too real world. it's better to have a sense of how particular recording should sound in your memory. something to guide you.
personally i've also found it helpful to stay as close to neutral as possible, as when a coloration is brought into the system then it must be balanced with another coloration or everything will have a sameness. and when you push the music to high SPL's any coloration or non-linearity will be multiplied and drive you back to less involving levels. big music demands things be right.
this is a part of finding a reproduction system you want to spend time with.
