Designers -who's been around the longest ?

I’ll clarify -when their career in design began. The (2) I mentioned are their current co.

Henry Kloss

Are you talking about electronics? All around? Bob Carver, still alive and still designing. James Martini (JBL & Altec) + James B. Lansing. I personally don't like Nelson Pass because he bought ALL the extra Sony V-FET transistors. People like me that own V-FET amps now have no replacement parts😒, but a good designer.

Any designer will do. Sorry to hear about the V-FETs. The bigger problem is what John Curl has been saying -HQ parts are not produced in good numbers anymore.

The exception are the new GaN-FETs-but these are output-only devices. MSB makes a terrific resistor-DAC but this is only one co.

John Curl has been around and active for a LONG time. He is correct about high quality parts.

It’s easier and cheaper for large quantity FET manufacturers to skip a few steps in production (especially baking time) to produce chips that still meet specs. But those specs don’t necessarily carry over to quiet / low noise audio components. And the quantities of chips required for high-end audio manufacturing doesn’t justify the added expense in manufacturing.

Keith Herron has also been around for a long time, since the 70s. He designed Crate and Ampeg musical instrument electronics before forming Herron Audio.