Levinson 300 series versus 400 series amps


I'm particularly interested in how the ML 334,335,336 stereo amps differ sonically from the newer ML 431 & 432 stereo amps. I realize there have been some posts on this subject, but usually people just say "X blows away Y". Instead I'd like to read more detailed comparisons.
ral
the 400 series is mostly for multichannel and it cost more because is new i have a 333 and it sounds wonderful and can drive any speaker no matter how difficult the load is also the newer 336 also sounds great enjoy the music
I heard a system with late-model 300-series and a set of brand-new 400-series monoblocks, and I couldn't tell the difference between them. AFAIC the difference is the 400-series are lighter, more compact, and put out a bit less heat.