obviously you are getting a lot of different advice.
I recommend you try different cables and maybe new tubes before selling anything as substantial as your amp or speakers. It is just plain easier to buy/sell wire or tubes than components. You can get big improvements with good tubes too. Also selling components you will probably take a bigger hit (money wise) than selling and buying wire etc...
Just my two cents and also fwiw you can chase your tail forever in this HFOCs (hobby for obsessive compulsives)
I recommend you try different cables and maybe new tubes before selling anything as substantial as your amp or speakers. It is just plain easier to buy/sell wire or tubes than components. You can get big improvements with good tubes too. Also selling components you will probably take a bigger hit (money wise) than selling and buying wire etc...
Just my two cents and also fwiw you can chase your tail forever in this HFOCs (hobby for obsessive compulsives)