As recommended in the owners manual, my Plinius 8200 mk II integrated is left on all the time (unless I won't be listening for greater than 5 days). Pliniius states the amp needs atleast 24 hours of warm-up to sound it's best.
Will leaving an amp powered-up all the time...
lead to "cap saturation" that causes the amp to sound bright? A friend sez yes. A listening buddy of his left his Spectral mono's on for three months and heard a difference when they had a normal warm-up.