The Luxman m900u SS amp is very smooth as posted above. I never owned it but I thought it was the smoothest SS I have ever heard.
I own an very smooth amp myself in the KRELL K-300i. Most comments I have read on old KRELL do not use smooth as a descriptor. However, this new KRELL with the XD feature on the amps are buttery smooth. A very enjoyable listen. I use them on some bright headphones than are uber revealing, a great match. The Luxman is warmer than the KRELL.
I own an very smooth amp myself in the KRELL K-300i. Most comments I have read on old KRELL do not use smooth as a descriptor. However, this new KRELL with the XD feature on the amps are buttery smooth. A very enjoyable listen. I use them on some bright headphones than are uber revealing, a great match. The Luxman is warmer than the KRELL.