This may or may not apply to the Krells but I was told a sign of electrolytics reaching the end of life is you can hear the capacitors make a faint sound when the amplifier is turned off. My old Adcom does that. The noise lasts only a second or so and it’s hard to describe but it is audible if you listen carefully. It almost sounds like you can hear the capacitors discharging. Just something i had read when a similar question was asked in the Adcom circles.
