BEST UPGRADE regardless of cost?


Changing my ARC VT100 MKIII for NAGRA VPA's. Like the difference between zipped and unzipped computer data.
jjwa
Perfecting the room acoustics. Made a bigger difference than any componant I ever bought or upgraded.
Re-thinking my answer, this time without regard to cost, I heartily agree with Warrenh. Other components have improved the sound of my system (some quite a bit), but nothing has increased the music I hear more than when I have upgraded my source.
For me the big one was the source, bringing my Linn Sondek Lp12 TT home back in 1983. It all gets back to, if you can't retrieve it in the first place, you'll never hear it with even the coolest speakers or amplifiers IMHO. Happy Listening!
Build a dedicated Audio room. You've never heard your system until you've done this. Get Rives Audio, Auralex, or ASC to help you and follow their recommendations. You won't believe the differnce.