I replaced mine with an MF2500A. Then replaced it with tubed amp and never looked back. But my speakers are 93.5db efficient. I’d say you will need min 60wpc for your speakers. Bob Latino sells an ST 120 w/ 60wpc for around $1800. It depends on your budget. I bought the ST 70 just to dabble in tubes. It replaced the 2500 Then kept it for 10 yrs. but i’m not much of n audiophile cause I don’t chase after utopia if I’m satisfied. You seem to be quite similar
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