Came and went so quickly?
Every large format Concert sound system using the latest technology are all using MOSFET power amps. Nobody uses Bipolar power amplifiers any more, only older systems....
We have retired all our BJT amplifiers.
So I guess I am just an old Dinosaur who will stick with the beautiful vintage units from the late 60's, 70's and early 80's.
I love collecting, repairing and restoring these older vintage units that use typical BJT devices
I just closed down my beach club for the season, and had to remove my "Sound System" from the Cabana
I use a recently restored Quad Pioneer (QX-747) so that I can easily set different volume levels for the pair of inside cabana speakers, vs the pair of Pioneer CS33a's that I use outside the cabana. Attaching a picture of the Pioneer Receiver, and notice the Akai GX head 8 Track unit on top that is a daily driver.
I used to install/service/support Business Sound systems, but that was a long time ago in the disco days, where sound was a lot more contained that at a modern "Concert". 2 or 4 big speakers like original EV Eliminators, being driven by a couple of Akai or Phase Linear Amps usually covered the place very nicely. Maybe if I was still active in the sound system business as I was in the 70's I would be using big Mosfet amps. But seeing that I am retired from my career running Big Bank Data Centers, and being 67 years old, I should stick to my enjoyable work with vintage gear. And besides, I probably couldn't move those heavy Mosfet amps around anyway.