BEST UPGRADE regardless of cost?


Changing my ARC VT100 MKIII for NAGRA VPA's. Like the difference between zipped and unzipped computer data.
jjwa
@khrys. I think your blanket statement on other AC power products is incorrect.   You might enjoy learning about balanced power from Equitech. Maybe :)
Spectral Pre and amp with MIT cabling. Spectacular improvement over the other “so called” top level equipment I had. I’m forever greatful to the well known,well respected Michael Percy (Audio) for his knowledgeable guidance. (PS for those unaware; both Spectral and MIT have extraordinary engineering talent whose expertise is respected by those in other fields :). 
Playing with speaker placement absolutely free, if you don't find improvement you can always replace to original location.