Defunct brands-


Do you or have you owned gear that, while you owned the piece- the company went under? 
I definitely have- most recently, Auralic. In the past- California Audio Lab. Both made good digital gear 

zavato

Paracas out of Carson City, NV.   Carl A. Staub was the owner and designer.   His amps were amazing, and he was a really fun ethical guy.   I have no idea what happened to him as I’ve lost touch.   His amps competed with Krell and Threshold back around 1980.   They had so much energy storage that I could unplug them from the wall and the amps would continue to play at volume for about 30 seconds.   I was lucky enough to own serial numbers 1A and 1b.

XStatic out of Oakland, CA.   Jason Daniels is still around and experimenting with new speaker designs and repairing his XStatic electrostats.   Great speakers and another great guy.  I still have my XStatic EC/1 speakers.

@pops dehavilland is still going strong, I believe. really well designed esthetics. 

http://www.dehavillandhifi.com/

Infinity as a high end speaker manufacturer.  In the mid-1990s they went mass market.  I owned one pair of their bookshelf speakers and then a pair of RS-IIb floorstanding models.  Awesome sound.