I owned VTL 250 mono's for several years and a good bud has owned the 450's even longer. The 250's are wired in triode and sound even better than the 450's when they're switched to triode and either will definitely get the job done; especially since you're only driving the top portion of your Vandy's and they're a pretty easy load.
I too am running a system that has powered subs and only use tube amps for my 89db, 6 Ohm main speakers. About 18 months ago I swapped my VTL's for a pair of 140wpc Atma-Sphere MA-1's and to say they were a huge improvement over the VTL's would be an understatement.
Everything is cleaner, clearer, smoother and much more refined. I'm getting way more information out of recordings, both cd and vinyl and the sound is just more believable. The VTL's sounded sorta muddy by comparison.
My main speakers are good down to around 50Hz and with the MA-1's, bass is fast and weighty but not exaggerated and more importantly, pitch and timbre are spot-on.
Both VTL and Atma-Sphere are well built and you'd probably be happy with either of them but the MA-1's will definitely take things up a couple notches.
Happy Hunting.
I too am running a system that has powered subs and only use tube amps for my 89db, 6 Ohm main speakers. About 18 months ago I swapped my VTL's for a pair of 140wpc Atma-Sphere MA-1's and to say they were a huge improvement over the VTL's would be an understatement.
Everything is cleaner, clearer, smoother and much more refined. I'm getting way more information out of recordings, both cd and vinyl and the sound is just more believable. The VTL's sounded sorta muddy by comparison.
My main speakers are good down to around 50Hz and with the MA-1's, bass is fast and weighty but not exaggerated and more importantly, pitch and timbre are spot-on.
Both VTL and Atma-Sphere are well built and you'd probably be happy with either of them but the MA-1's will definitely take things up a couple notches.
Happy Hunting.