I have an Audio Space AS-3i with a triode/ultralinear switch on the front panel. This is my story...
I've used both EL34s and KT66s in this amp. With the EL34s there was more power available, of course. I ran the amp all the time in triode mode because I found the sound sweeter and more detailed. With KT66 tubes the difference between triode and ultralinear was less obvious. I used ultralinear for the extra power. FInally, though, it began to appear that triode was the nicer one even with KT66s.
Having a switch on the front panel is really useful. There are some discs--rockers, full orchestras--which get a needed boost in impact with the extra power of ultralinear mode. But in the end it's a bedroom system and I do most listening in triode.
I've used both EL34s and KT66s in this amp. With the EL34s there was more power available, of course. I ran the amp all the time in triode mode because I found the sound sweeter and more detailed. With KT66 tubes the difference between triode and ultralinear was less obvious. I used ultralinear for the extra power. FInally, though, it began to appear that triode was the nicer one even with KT66s.
Having a switch on the front panel is really useful. There are some discs--rockers, full orchestras--which get a needed boost in impact with the extra power of ultralinear mode. But in the end it's a bedroom system and I do most listening in triode.