Pass Labs Int 25 vs Int 60

I have had 2 pass with my Wilson Sophia 2 (89db min 3ohms). Very revealer speaker. Int30A (60w class A at 4ohms), Int60 (15W Class A at 4ohms). I chose the first. It’s a warm sound with necessary detail and information without being fatiguing. I’m surprised how well the Wilson drives, I guess being 4 ohms doubles the power to 60 watts pure A which is brutal, generating the pressure of a live concert. Int60: instead I feel that it has less grip on the bass and generates more fatigue. at mid vol The needle starts to move quite easily because it leaves the class A and the distortion of the class AB is heard.

I would like to try the new Int25 (pure A)

I listened to several Pass Amps (X250 X250.5 X350) and I feel that I like only the pure class A line of them.

If anyone is interested I have nude photos of both of them on my channel. @Mat_audio

It comes down to the load the driven speaker represents. 

If you want class A sound one must stay in class A. Though the XA25 or Int25 can produce greater than the stated 25 watts when needed, the amp is no longer biased in class A. Thus some of the 'sweetness' is lost. 

I own the XA25 and love it. Drives efficient speakers in a ~15'x12'x8' room.  

Hi All! According to your experiences, for lower volume listening (55-60dB) would INT-25 be sufficient to drive speakers with sensitivity 91dB at 6ohm?

@kastor77 I would think so unless the room is quite large. Sensitivity specs for speakers are often reported  higher than actually measured under real world conditions. 

I have driven my Esoteric MG-10s with the XA25 in a 12x15' room with no problem. They are 6ohm nominal, drop below 4 ohm somewhere at lower frequency, and 87-88dB sensitive. 

Thank you very much @mesch for your response. My room is 16x23’ and the speakers go down to 3.31 ohm.