It's hard to be both analytical and musical, isn't it? I would say that Pass Labs is more musical than Bryston. Bryston is more like Mark Levinson in my mind, but I am a tube guy (Audio Research) so most everything solid state sounds pretty lean to me... (I have a pair of ML No531H monoblocks but personally much prefer my ARC Ref 250SE monoblocks.)
Bryston
Tonality: Clean, neutral, and highly linear. Bryston amps are often described as having a “studio monitor” approach — revealing and "true."
Bass: Tight and controlled, sometimes described as “dry.” Not overtly warm or lush.
Midrange: Accurate and clear, but can sometimes lack the richness or dimensionality that tube-like or Class A designs deliver.
Treble: Crisp and extended, but with a focus on precision rather than silkiness.
Dynamics: Fast, punchy, and capable of high SPLs without stress. Excellent transient response.
Soundstage: Wide and precise, but not always the deepest in the absolute sense.
Character: Analytical, with a “get out of the way” transparency that appeals to professionals and those who prefer uncolored sound.
Pass Labs (closer to the ARC sound I revere)
Tonality: Rich, smooth, and slightly warm. Even their Class AB amps retain a touch of the signature Pass warmth.
Bass: Full-bodied and weighty, though not as surgically controlled as Bryston.
Midrange: Lush, holographic, and inviting. One of Pass’s standout traits.
Treble: Smooth and refined, never etched. Some might say slightly rolled off compared to ultra-analytical designs.
Dynamics: Organic and flowing rather than ultra-snappy; more about nuance than slam.
Soundstage: Expansive with exceptional depth and spatial layering — often described as “tube-like” in this regard.
Character: Musical, emotionally engaging, and seductive. Pass Labs aims for beauty and realism over strict neutrality.
Is one better than the other? Horses for courses...it's what YOU like that counts.
(Sorry, don't know much about the other brands.)
Rock On!
