Best bang for the buck


What’s been the most cost effective item you purchased for your system? 
I will go first- a Zerostat I bought 40 years ago. Next most cost effective purchase has to be a Denon DL103R cartridge which I bought new for $300. 

zavato

Dirac $299.  After that it would be the several thousand I spent building acoustic panels.

"Dirac $299.  After that it would be the several thousand I spent building acoustic panels."

Nothing left over for head reduction surgery?

 

Nothing left over for head reduction surgery?

Some posts reduce brain matter

Yamaha NS-5000. You could spend ten times the money and never match the driver technology.