PSB Synchrony One Speakers and Pass XA30.5 Amp

ARC is a good choice, but understand that my recommendation of changing speakers and keeping the Pass is due to my belief that there are many speakers better than the Synchrony to build a system around. I owned both the One and Two, and PSB discontinued them pretty quickly and introduced a new line of speakers.
 A Pass based system with the right speakers would be a step forward.

Perhaps, start a new thread and you will get responses from tube guys and Pass Class A owners who can recommend an efficient speaker that excels in jazz and classical reproduction.

Good suggestion, lowrider57. I will do just that. Thanks much!

Just like any other "which speaker" question, you'll get dozens of different responses. Make it more difficult, there's a whole another divide between classical and jazz content which tend to be polar opposites as far as speakers go. And to top this of, ~$4K is another  sweet spot for speaker options - just like $2K, and sky is limit in terms of options. Double your search if you are open to used. Enjoy the journey. 

Look for a more efficient speaker (over 90dB sensitivity), preferably 8 ohms, which rules out Dynaudio, Totem, B&W.
Kef, Klipsch, GoldenEar are efficient speakers that can be driven by tube amps and are more transparent than PSB. Even if you were to move to a more efficient PSB model, I don't think their warm sonics would match well with the Pass.

Perhaps, start a new thread and you will get responses from tube guys and Pass Class A owners who can recommend an efficient speaker that excels in jazz and classical reproduction.

Why change the amp? I suggest auditioning some speakers that are more efficient and are more neutral. PSB's are toward the warm side, which is not a good match for the Pass Class A.

I'm willing to consider alternatives to the Sychrony One. What can be recommended in that price range, say, up to about $4k used? Has to be full range and good looking. And good with all kinds of music, but jazz, vocal and classical, especially. Ideally one known to match well with the Pass XA30.5.

I have heard those PSBs paired with Bryston monoblocks and they sounded quite dynamic and very musical. Aside from your room configuration - on that later,  your issue as said before could be a matching issue. Your space arrangement seems to suggest you have a ~14' open space behind your listening position which could be a problem. Your 16' ceiling is another potential culprit. Also, I had a very similar experience but with completely different components where I had a real long and narrow room with tall ceiling and I could never get the near-field set up work for me using basically half of the length of the room. I moved everything to a smaller (repurposed) bedroom - 8' ceiling but the same exact distances for near-field listening and it all came alive. Try some temporary room treatment, especially behind your listening position and see if it makes a difference. Finally, looking at the measurements for these PSBs, a large portion of frequency band operates in 4 or less ohms - particularly the area where most of the music energy lives so by all accounts these speakers are putting a high demand on your amplifier's power supply.

Why change the amp? I suggest auditioning some speakers that are more efficient and are more neutral. PSB's are toward the warm side, which is not a good match for the Pass Class A.

Are you getting 3D imaging and wide soundstaging? You should be with that amp.
Lastly, what are your speaker cables?

lowrider57, not really remarkable imaging or soundstaging (I've had better in another system in another house.) Space constraints limit the speaker-to-front wall distance to less than 2ft. I sit as far back as I can so increasing that distance means even nearer-field listening. I do have them about 7ft apart, though, at least 2ft from the side walls. I'll try re-positioning. Speaker cables are Wireworld Equinox 7 (I also have Anticables Reference 3 which don't sound noticeably different from the Wireworld.)

Did the PSBs ever have the vitality you want, driven by any other amp?

mechans, I only tried them with a Hafler 9500 which didn't sound quite as good as the XA30.5 (even though it was much more powerful at 375W/ch into 4 ohms) so I sold it and kept the XA30.5.

If you seek greater liveliness, it could be an amp/speaker mismatch, in which case I would change the speakers, or it could be that you need a preamp with a little bit more life.

jmcgrogan2, this is what I suspect (amp/speaker mismatch) although I still have a pair of Infinity Renaissance 80 which also lack liveliness with this amp. They don't sound quite as good as the Synchrony One with this amp, though. This makes me think the XA30.5 is too warm of an amp. I'm thinking about searching for something else to try.

Have you considered there could be an issue elsewhere? Would you care to list your entire system? What is the source? Sometimes power conditioners can make a system sound dull. Are you using one?

tls49, my source is a dedicated NAS feeding a Squeezebox Touch whose digital outputs feed a PS Audio DL3 DAC (which drives the Pass XP10 preamp.) I use no power conditioning. I also have a Denon DCD1650AR CD player and I've tried driving the XA30.5 directly with that from its variable outputs (eliminating the PS Audio DAC and Pass preamp) and matters don't change greatly. I only decided to try this yesterday so I'm still auditioning things this way.

Thank you all for your comments. If I had to try another amp what might I look for? I don't do tubes.

mechans brings up a good point. Have the speakers ever had this "liveliness" that you are looking for? The speakers may benefit from more power, but I find it hard to believe the XA30.5 is solely responsible for the issue. Stereophile's review on the amp measured 130 watts before clipping into 8 ohms, 195 watts into 4 ohms, and over 330 watts into 2 ohms. This is a beastly 30 watt amp. Have you considered there could be an issue elsewhere? Would you care to list your entire system? What is the source? Sometimes power conditioners can make a system sound dull. Are you using one?

I agree that the XA-30.5 may not be the perfect amp for those PSB speakers. However, there are other factors at play. Pass Labs gear tends to be warm and musical, so combining a Pass preamp with a Pass amp may be too much warmth and not enough detail.
Many Pass amp owners use an ARC preamp, like myself. The ARC provides a bit of speed and resolution to the musicality of the Pass amp.

That said, I'm still not sure that the XA-30.5 is enough power to drive your speakers. My room is 24 (L) X 15 (W) X 9 (H), my speakers (90 dB, 5 ohms) are a bit more efficient than yours ( 88 dB, 4 ohms), and I am running XA-100.5's, which provide plenty of power. 
If you seek greater liveliness, it could be an amp/speaker mismatch, in which case I would change the speakers, or it could be that you need a preamp with a little bit more life.

Did the PSBs ever have the vitality you want, driven by any other amp?  If so you know they can do it,.  Now you have to decide whether you want to design the rest of system to get that out of them.  I went through that with some Focal Electras and was quite happy with the result.  It literally to years of trial and error to get there  though.  If you haven't heard them do it in another system then I would ditch the PSBs, and go on the "perfect speaker" hunt.  The bane of all audiophiles known to take down even the high and mighty.

It seems like you are listening in a near-field setup, so room acoustics may not have an effect. Make sure the speakers are at least 3 ft. from front wall and play with distance from side walls. I needed speakers to be 7 to 8 ft. apart and toed-in.

Are you getting 3D imaging and wide soundstaging? You should be with that amp.
Lastly, what are your speaker cables?

@partialresponse , I would think that the Pass XA30.5 could drive this speaker with its high current, but there have been past threads where somebody had described the same situation with the Synchrony One. Basically complaints of lifeless or non engaging music.
This is a demanding load where impedance drops to 3 ohms and below. The speaker is rated at 4 ohms, so the Pass should double down to 60 wpc/4, correct?

Maybe it doesn’t pair well with Class A, just a guess.

I typically listen at very moderate levels and the lack of dynamics to which I refer are at such levels. I wouldn't have thought insufficient power would be an issue at such moderate levels (the bias meter on the amplifier barely moves.) And although the Pass is rated at 30W/channel into 8 ohms it is much more powerful than those 30W a side suggest.

Synchrony One is not an easy load to drive.
http://www.stereophile.com/content/psb-synchrony-one-loudspeaker-measurements#Tg4MUvgRPY2suIrQ.97

Without high power, high current it will never sound dynamic. Maybe a high power Pass, Plinius, or Parasound A21. I had 600 wpc/4 ohms driving mine. 
This speaker can sound dynamic with deep bass extension, very wide soundstaging, with warmth. Not the most transparent speaker, maybe Class A is colouring the presentation.