SET amp comparable to First Watt SIT 1?

tmare - fwiw, I used the SIT-2 and SIT-1 in a large space like yourself and like to even crank electronica at times. I would recommend more wattage like 213Cobra suggests.

I think if you are considering SS, you might look at Pass XA-30.8 which you can audition from Reno Hifi. There also is a pair of Sophia Electric 845 amps on this site which can get you into good SET relatively cheaply.

@charles1dad  I'm good with that- that's how I would describe it too. You expect an SET to sound fuller as it has more 2nd harmonic distortion where the MA-1 really does not have much at all. I think that if you had a sound pressure level meter in the room, you would have found that although you were careful to match the volume of both amps by ear, that in reality the MA-1 was actually playing at a higher level.

The leaner sound our amps often have is simply that they make less distortion (most of it being the 3rd harmonic, at about or slightly less than an SET will make at the same percentage of power level with respect to full output).

When designing any kind of amp its all about the distortion it makes as to how it will be regarded. For example solid state amps have a lot less distortion but what they do have tends to be higher ordered harmonics which the ear translates as 'bright' and 'hard'; for a solid state designer its the 7th harmonic that is the one to be avoided if possible. I figure those are the drop dead harmonics to avoid if you plan to play the system for hours and hours on end. That way you won't get fatigued.

Atmasphere,
Yes , I've heard the distortion argument rendered many times and that may in fact explain to some degree what I am hearing.What is interesting is the fact that the SET consistently sounds more real and closer to what I experience at live unamplified venues. That's why I just follow my ears and choose what sounds right and more life like. Again we all will listen and make our personal choices whatever direction that may be.
Charles

^^ I get that. I played string bass in the orchestra for years. On that account its always been really important to me to get the bass right. That's an example of my own preference. But because I played in the orchestra I really really don't like it when the system sounds 'loud'. That bugs the heck out of me. I want it to sound effortless even when I'm play real volumes like I've heard in the concert halls with acoustic instruments. Somehow the orchestra could sound effortless and not shouty even though it was playing at 100db! Picky I guess...

Thank you for a lot of precious comments again. Many interesting read as well.

I feel that I should tell you guys my question has been already answered by great members here at Audiogon, thank you!. I wanted to know which 300B SET would be the best candidate to be compared with SIT-1, and I got a lot of (too many?) great recommendations. This holiday season, I’ll research more about SET and horn speakers (it’s a fun time), and I’ll report what I finally choose. (or I’ll have to post the other questions...)

Happy holidays!