Pass X150.5 vs. X250.5

A Vandersteen 3A? In that size room? You might be underpowering, but I would think one is listening too loud if that is the case with an X150.5 - no? - I mean, that is a lot of power for that speaker especially a 87db /nominal 6ohms (I would think)

Ok, meter does not exactly BOUNCE, but the does move up from its static position at 9:30 to about 11:00 when it is at it's loudest. Doesn't really seem TOO loud, but that's a matter of opinion, unless it's causing hearing damage..... Anyway spoke to the folks at Pass Labs today and they said I COULD be running out of power, maybe the X250.5 is the way to go but borrow one first and see if that changes things. Sensible, those guys. They felt that meters hitting 11:00 was close to running out of power. I was kind of surprised at that, but who'd know better than them? Anyway they also suggested a change of wire to the upper section of speaker an another way of taming any harshness, but I don't think that would really help based on other cable I have used in the system. Just as an aside I originally had a pair of Aleph Os, but I sold them for the 150.5 to get more detail and dynamics, and that was exactly what I got. Another reason for looking into the 250.5 is that there are currently 2 in NJ on the list, and that's where I am, so It'd be very simple for me to buy one of them. Thanks for the info so far guys!

Once again, I think you are running out of power in class A mode, not total power. You indicate that when you turn it up, it gets bright and grainy (my words), this is indicative of these Pass amps that transfer out of class A to class A/B, in my experience. The 250.5 isn't giving you much more power in class A. I understand your desire and goals in moving from the Aleph series to these, but I think if you want to stick with Pass, you need to step up to more power in class A, even if it is less overall power in A/B to get the results you want, louder volume without the sound falling apart while achieving the more detailed and attachs that you felt were lacking in the Aleph series (with its more tube-like sound in comparison and its SET based design).

I still wouldn't rule out the room as a contributing factor. Some rooms can handle a certain volume or SPL level and exceeding that level can have consequences that aren't as noticeable at lower listening levels.

Interesting theory about the room. You could be on the mark there as there are absorber panels between the speakers on the front wall,and a panel at each first reflection, but nothing behind the listening chair and nothing on the ceiling, although one can go to far there too. Thought the live end-dead end theory was at work, but I'll try some absorption in the back too. Also understand where you are going with the class A amps. I was thinking in terms of total power, not class A power when I thought about the 250.5. I'd probably need at least an XA 100.5 to make it work in class A, but that is WAY above budget.

I would not rule out XA60.5s being able to drive the 3As to VERY loud levels - but, still expensive.