need your help on this one.....

I have owned both the SA-103 which is  class A, A/B switchable and the SB-301 class A/B. I you like big dynamic sound especially with less than efficient speakers, go with the SB-301. It offers a much punchier and defined bass and overall more control in my opinion than the SA-103. I'm driving Legacy Focus 20/20's and get huge sound from the SB-301. There is an article somewhere that states, power is everything. I really believe that reserve power is important for defined transient response. I cannot speak to the Pass line.

thanks falcon for your reponse.....and yes I do like a dynamic sound with great sonics and sound staging.  what kind of preamp do you recommend with the sb 301, I have Conrad Johnson gear now. 

I would go with the Pass 350.8 great products and company. No experience with Plinius although I have heard they are a very good company. And as someone mentioned above Pass will more likely hold its value better and be easier to flip if you decide to move on. You can contact Mark at Reno Hi-FI and take advantage of an in home trial; no affiliation.

I have Pass xa100.5’s with a Pass XP-20 and they are excellent performers.

Chuck

czbbcl, I'm familiar with neson pass gear from my adcom days.  hear a lot of good things about his line.  but is very expensive.  am leaning to the 3
50.8, but have heard the 250.8 has better sound quality.  how is it on heat and the electric bill, do you have to leave it on 24/7.

The XA mono-blocs being Class A topology do get rather warm. I will not say hot as I have had tube amps in the past and those do kick out a lot of heat. I do not leave them on 24/7 instead turn them off when I retire for the evening. When I first got the amps I noticed the electric bill went up a bit maybe 5%. I know Pass does bias the X (AB topology) line higher into Class A than most manufacturers do so it will get warm. I have heard the same thing said about the 250 vs 350 but I have no experience with either amp so I can comment.  I would talk to Mark he is a straight up person and can give you a better idea of the sonic qualities of both. 

Chuck