Lancelock,
The unique experience with the Berning design is probably because DB himself is just smarter than anyone else in the industry. Quiet and modest, as well. (I have met him a few times in my life, but I have none of his gear currently, and I have no financial interest in his success.) A few decades ago, one of my friends purchased a Berning amplifier (I think it was an EA230), and he had it placed right next to his Modulus preamplifier, in a cabinet. (At that point in time, DB was known to us as a local genius designer.) We could hear the switching noise over the speakers, until we moved the amplifier a few feet further away from the preamp. Since that one experience, I know of no instances where switching noise has been a problem with a Berning product. My friend ended up with a pair of Berning ZH270 amps running his Acoustat speakers. I auditioned the same pair of amps on my own 'stats. They were dead silent in both venues.
The unique experience with the Berning design is probably because DB himself is just smarter than anyone else in the industry. Quiet and modest, as well. (I have met him a few times in my life, but I have none of his gear currently, and I have no financial interest in his success.) A few decades ago, one of my friends purchased a Berning amplifier (I think it was an EA230), and he had it placed right next to his Modulus preamplifier, in a cabinet. (At that point in time, DB was known to us as a local genius designer.) We could hear the switching noise over the speakers, until we moved the amplifier a few feet further away from the preamp. Since that one experience, I know of no instances where switching noise has been a problem with a Berning product. My friend ended up with a pair of Berning ZH270 amps running his Acoustat speakers. I auditioned the same pair of amps on my own 'stats. They were dead silent in both venues.