Most enduring audio purchase

Aerial 10T. They sound very natural and strong. So far I keep them near decade already without no upgrade plans whatsoever.

My Great American Sound Thoebe preamp and Son of Ampzilla. These were my first high end equipment purchase and I have held onto to them after going through many different preamps and amplifiers, not to mention speakers. I have recently had them updated and upgraded and the GAS house sound is still there but in a more refined way. They hold their own against present day equipment. Besides, I like having meters on the amp even though they are meaningless.

Magnepan MGIIIa speakers! Purchased in 1987 for $1995 and still in use in my home theater. My main speaker up to 2004 when I bought Magnepan 3.6's.

Deep, clean sound from 30 Hz to 40 Khz. Sounded best with GAS Son of Ampzilla, Audio Research D125, and Spread Spectrum Son Of Ampzilla 2000 power amps.

Beautiful 3D, clear, natural sound.

Best sound per dollar I ever spent!

Meadowlark Audio Kestrels; one of my earliest purchases when this whole internet buying spree, merry-go-round began for me. They will be given away when my hearing goes.

Van Alstine Super PAS4i preamp about 20 years old with 2 Amperex 12AX7's in line stage and 2 RCA cleartops in phono stage.
About 20 years old, brought in into Frank about 2 years ago and said make it as good as you can, which he did.
MUCH better than my Bryston BP-6 and save a tad in bass the equal of my EE Avant.
Only 11 inches wide which I like.