Pass Labs amps. Help me choose.


Speakers: Focal JM Labs Electra 1037BE
Room: 15 x 20 x 10 (w x d x h)
Listening Volume: typically 70 - 80 db at listening position. occasionally peaks at 90 db with symphonies (Mahler, Tchaikovsky). Rarely if ever above 100 db.

First a little background. I had an opportunity to audition X-150.5 at home, and I instantly fell in love. I have a stereo + multi channel music system, and I need five channels of amplification. I have immediately acquired X-3 for center and rears, and have been looking to get X-150.5 or X-250.5. In the mean times I was using X-3 for fronts and center duties. I had B&W Nautilus 804 speakers back then.

Fast forward a few months, I have replaced B&W with Focal Electra 1037BE. Focals are wonderful speakers, but it turned out they are a mismatch for X-3. When driven with X-3 the tonal balance is noticeably lean. X-3 couldn't control the bass and dynamics, and loud transient became muddy. Not a big deal, as my intention was to use X-3 for center and rear anyways, but I still needed amplification for the fronts. I've then acquired Levinson No 335 to drive Focals. With Levinson the bass control and dynamics are back.

Objectively, No 335 is an excellent amp and I could happily live with it for a while. However I am still partial to Pass Labs, and I would like to get a proper Pass amp for my speakers and compare against my Levinson. I do miss the musicality and the ease of flow with the previous set up with Pass amp. The amps I'm currently considering are the following:

X-350.5
XA-100
XA-100.5

X-350.5 and XA-100 are within my budget. XA-100.5 is a somewhat more than I would be willing to spend on amps. But if it comes down to only XA-100.5, then I am willing to take a leap.

Obviously my primary concern is whether the amp can drive my 1037BE. They are not an easy load where the impedance swings from 3 ohm in low bass to 18 ohm in upper midrange. X-3, a sibling of X-150, had problems driving my speakers. Personally I would choose XA-100 if it doesn't show the problem X-3 did and can drive my speakers with correct tonal balance. I don't know if it can or can't. X-350.5 looks great too. Two concerns with X-350.5 is that I don't want to pay for the powers that I may never need (350W @ 8 Ohm and 700W @ 4 Ohm is really a lot of power), and I may later regret not getting the XA series and just "settle" with X series. Then XA-100.5 would probably be perfect, but with about 2x the cost.

That's where I'm at right now. If you own any of the models listed above please let me know what speakers it's driving, and how you like / dislike about your amp. Thanks,

jlee
jylee
i had an e-mail exchange with a gentleman at pass labs about the xa.5 amps. and he "really" liked the xa100.5, so that would probably be something to save up for. BUT IMHO your levinson should sound (overall) as good as any of the non-XA amps you are considering- stronger in one area, weaker in another, etc. but still a great amplifier. or you could "feed" the 335 a warmer/better signal to get it to lean more in the XA direction. then again, if i can't talk you into liking what you already have, things might get very expensive. i have a pair of ML-33H's, and after ALOT of thought about upgrading a few months ago, i simply put on several different types of music, and my doubts just melted away. my brother still has his pass aleph amps (1.2's), and has the same "problem"- they simply sound fantastic, alblum after alblum. of course they're "old" and "discontinued", etc. as a final test of your present system, i humbly suggest that you put on some "emotional" music and see if you find yourself becoming deeply involved in the experience.
Yes, the XA-100.5 will be perfect for your setup. The .5 amps will solve most all your speaker load/power output needs. Call Reno HI-FI.
what is the sensitivity of your speakers? if less than 87, you may want to try the 250.5 (i have them running a pair of magnepan 20.1s and it is excellent). i think it would be enough power because the sensitivity of my speakers is 85db. the 350.5 might be overkill and the xa100.5 might not be enough. i can tell you that the x250.5 is more tube-like in quality compared with the x250 i used to have. i know this throws a monkey wrench in your situation, but it is something to consider that would save money and not compromise sound. you are right about the pass sound though, it is the best in the world.
X250.5 may be the right choice. Unless you want to spend more and get the XA series amp.
Also, with X350.5 you do get more power overall that you may not use to the fullest, but you also get more Class A power than X250.5 provides. So that is also something to consider.
But overall I would think that X250.5 is all you need.