What's the best and/or favorite piece of equipment you've owned? And do you still own it?

Audio Research Ref 10. The most gorgeous sound. 

No longer own it. Heartbreaking.

I still own them.

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My McIntosh XRT 28 speakers. They’re never leaving my system. I just love their sound and looks.

Another piece I’ve had for a long time is a Pioneer VSX 505S (bought in 1996 for $320). It’s not high end, but it’s my daily home office receiver that’s still running strong after 24 years.

I would have to say it is a tie between my newly refurbished all black Revox PR99 and my custom made Grandinote Mach 36 speakers (from Italy).  There is something quite soothing and magical watching those 101/2" gold reels spinning while generating great music through those giant speakers, each with 36 drivers and 25 tweeters.  I love the rest of my system (500 level Naim amp, pre amp, CD, phono stage) but the R2R is sublime.  Oh, I almost forgot about my Kuzma Stabi XL DC turntable with the 14" tonearm and Koetsu Rosewood Signature Platinum cartridge.

Pair of mono blocks made by a local guy Dave Herrin (Portland Oregon).  They just keep playing good music.