Brands That Died

I used to be fascinated by loudspeakers from Polymer Audio Research, which I believe is defunct now.

Tice -- The clock was roundly mocked, but their power conditioners had tremendous build quality.

@goofyfoot 

"I sometimes worry about my ASR amplifier and what will happen if the designer decides to retire. Its such a small company and the amplifiers are made to order."

If the amp was designed based on established principals and made to last the only thing you would need to worry about is sourcing adequate tubes when you need them. History has shown that all legitimately manufactured tube components stand the test of time and remain serviceable for decades and decades. The main issue is finding technically accomplished individuals to work on them should they require repairs.