Waiting for my 509u, I tried the 20wpc pure class A 550AII with my B&W 803D.
It was clearly not enough for my speakers (good only at late night volumes) but I heard it with smaller and more efficient speakers (Living Voice) in my dealer's showroom and it sounded very well, very musical.
Luxman class AB (505u,507u and 509u) are different from class A integrated amps (550AII and 590AII).
Don't expect from a pure class A i.a. great control at louder volumes driving difficult speakers with rock or classical music, great detail and absolute neutrality.
On the other hand you can't ask 509u the warmness and musicality of the 590AII.
Luxman, that's to say, demonstrated both 509u and 590AII at Tokio International Audio Show with B&W 802D speakers, even if it's clear that 509 has better driving capability.
It was clearly not enough for my speakers (good only at late night volumes) but I heard it with smaller and more efficient speakers (Living Voice) in my dealer's showroom and it sounded very well, very musical.
Luxman class AB (505u,507u and 509u) are different from class A integrated amps (550AII and 590AII).
Don't expect from a pure class A i.a. great control at louder volumes driving difficult speakers with rock or classical music, great detail and absolute neutrality.
On the other hand you can't ask 509u the warmness and musicality of the 590AII.
Luxman, that's to say, demonstrated both 509u and 590AII at Tokio International Audio Show with B&W 802D speakers, even if it's clear that 509 has better driving capability.