Which purchase tipped you into nirvana.

After owning some excellent gear, which purchase was it that put a big smile on your face?
After 30 years in this hobby, I have found one piece that I think qualifies in answer to your question: the Berkeley Audio Design Alpha DAC. When I found this, I was about to despair over Redbook CD reproduction. Now I think I may be close to the end of my search for a truly musical sounding system.
Usually every new piece of equipment I buy! Or even rearranging my old equipment can have unexpected pleasant suprises.
Each piece was an integral step forward, but I do not think I could get there with my budget without the modern OHM Walshes.