I just purchased their PASSION 650 stereo amp. Some of the sweetest solid-state Watts I have heard; this is after letting go of my BEL CANTO 40 SET AMP.  Given how wonderful YBA products are I am wondering why I’ve heard of them only once or twice in the last dozen years or so, and I think both times have been me. Anyone out there have first hand listening experience with YBA?
Of the two AR systems - each with CDP, tuner, and integrated amp - one tuner died (easier to replace than repair) and one amp needed repairs. Both CDPs are alive and well. 
Good to hear from you  @warrenh.

That Bel Canto amp is no slouch! I will check out YBA again.

Indeed. The Bel Canto, as you say, was no slouch but the YBA top to bottom rings truer to my ears. It is uncanny how much  it sounds like a tube amp. And the power really provides something my SET could not do. is The Black Keys Gold on the Ceiling, Gregory Porter’s Holding On and Pink Floyd, Time to name a few. It’s a very personal thing, but the Woodstock baby in me sometimes loves to go to hard rock ear bleed quality levels. Btw, I am still using my Bel Canto SEP 1 modified SET preamp. It’s nice to be back on the ‘gon
I had a YBA 2 pre amp.
It was dead quiet and nicely refined, but not super special.
Of course that was 20 years ago.
I also have the Audio Refinement integrated amp and CD player. It's an incredible combo. The build quality, attention to detail, sound...all top notch.