I wouldn't get caught up in the solid state vs tube discussions. Simply come up with a list of equipment in your price range, go listen to them, regardless of whether they are solid state or tube and decide what you like from there. If you fall into the prejudiced arguments, you really are hurting yourself as there are some great solid state equipment and alternatively some great tube equipment. Decide by closing your eyes, play your favorite music and decide for yourself. $20k to $30k isn't bad at all, especially if you don't limit yourself to new equipment and are open to used. Since you want computer audio, I would expand it a bit to include a separate DAC capable of USB input. Anyway you look at it, take your time, decide ahead of time where the equipment will be located in your room and run as many (at least three) dedicated lines (separate ground, neutral and hot per dedicate line as you can while the walls are down) and enjoy the hunt with no stress.
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