Your single favorite component

My Accuphase E-600. I'm still shocked I own it and even more so when I'm listening to it.

Koetsu stone body cartridge. I've had 4 now, and the best one is definitely my new Coralstone. But all of them do much of the same thing -- i.e. everything I want from a cartridge.

It's the only component that sounds really good even on its bad days. Sounds spectacular on good days, and most days are good days.

Honorable mentions:
Tannoy Canterbury SE speakers, Stax SR-009 headphones, Head-amp Blue Hawaii SE headphone amp.

it's tie
Timbre TT-1 DAC
S.A.P. Anniversary mono blocks

My Acoustic Zen Crescendo speakers. They are not fussy and have a full bodied sound that is so inviting. At both low and high volumes they just sound right to me. 

My yba passion 100 integrated hands down!