It's not that SETs, per se, can't handle large-scale orchestral music, it's more the case of people trying to couple inappropriate speakers to low-powered SETs. I have no problems with 8 watts of SET power (parallel 2a3s) on 99 db/w efficient speakers that are an easy load. I also get reasonable volume level with a pushpull 45 amp (about 3 watts). Both can do the closing minutes of Mahler's 8th at reasonably realistic levels.
By the way, I think choral music is a much harder test of output cabability for most amps than orchestral music. At surprisingly low subjective levels, choral music can start to sound strained and rough. Try Rachmaninov's Vespers, as an example of this phenomenon.
By the way, I think choral music is a much harder test of output cabability for most amps than orchestral music. At surprisingly low subjective levels, choral music can start to sound strained and rough. Try Rachmaninov's Vespers, as an example of this phenomenon.