LTA Ultralinear Plus Integrated vs. Pass Labs XA25/EAR 868pl

I own both of these amps and can swap between them fairly quickly. I use them with Spatial Audio M3 Sapphire open baffle speakers (4 ohm impedance, 92 db sensitivity) in a 13’X16’ room. Source is 100% vinyl (Kuzma Stabi R/4Point11, Etsuru Urushi Cobalt Blue/Luxman EQ-500/Allnic AUT 2000 SUT). I listen mostly to rock, jazz and folk, and at a decent volume (85 db A-weighted peaks).

Since these are well-known pieces of kit, I will limit my comments to a  sound comparison. I’ve had the XA25 for a year, and prior to that, an XA30.5 for four years. I’ve only had the LTA a couple of months.

The LTA has a big sound with an expansive soundstage that seems to wrap around you whereas the XA25/EAR combo seems smaller but more nimble by comparison. The LTA’s big sound doesn’t come at the expense of detail. In fact, certain “decorative” sounds like bells, triangles and non-drum percussion seem to stand out more with the LTA. Same with vocals, which are quite forward in the mix and, possibly, not to everyone’s liking (personally I prefer it). The XA25 wins on dynamics. In fact, with the Spatials, for me, this is one of the best things about my system. But the LTA is entirely satisfactory in this department as well. Finally, to my surprise, the LTA has amazing, addictive bass that makes the Pass Labs (which until I heard the LTA, I thought produced more than adequate bass) seem anemic in the lower registers. I like the Pass Labs bass enough that I don’t use my subs. With the LTA I would say the bass I get might actually be too much for some ears. Subs are absolutely not needed.

I’ve had tubes in my phono pre and linestage for a long time but the LTA is my introduction to tube amps. The reason I own it and the Pass Labs at the same time is that I wasn’t convinced buying the LTA was going to be an improvement so I held onto both. It’s possible that the EAR is holding the XA25 back and/or the LTA preamp is superior to the EAR. The only way to find out would be to try another preamp with the XA25, which I may do. Honestly, the David Berning design of the LTA seems to provide the best attributes of both tubes and solid state, in an incredibly small, light package. Does magic exist in audio? I think so.


@tangramca I was wondering maybe my issue was the Z40+ had too much power and when I was driving them at lower volume they suffered.  The lower power models ,like your UL, when driven at a higher amp level might be the ticket to better bass and meat. The Z40 sounded great when driven at higher volumes which I can’t live with.  Just 🤔 


the m3 sapphires certainly did not work me, glad they are working for you

i have not had the smaller lta ultralinear amp, sorry, so i cannot comment directly on that... i have quite a store of old stock british and dutch el34 and kt77 tubes from the good ol days, so the zotl ref amp is a natural for me, not to mention the additional power output this upper model affords -- i am actually getting a second zotl ref so i can run them as monoblocks!

It’s interesting - when I post about LTA’s Ultralinear amp, most who have had LTA gear invariably say they own or owned the Z40, not the UL. Not sure why. Extra power?

I think the power rating explains this—people generally think more is better. But these two amps sound different. It’s not simply a matter of more of the same. LTA calls the UL “more refined” and it is—more detailed, nuanced, magical. If you don’t need the extra grunt then the UL is your boy.

@dodgealum interesting. I agree that the detail is there in spades. I don’t have much experience with tube power amps so I wasn’t really expecting this. How would you compare the bass of the two amps?

@tangramca  Like most low powered amps (but perhaps to a lesser degree) I think the bass response of both LTA amps is really system dependent. I don’t think either amp is for every setup. But if your speakers are reasonably efficient and present a fairly modest load they are among the best available, certainly at their price (and well beyond). The nice thing about working with LTA is the opportunity to try them out and see which you prefer and how they perform with your speakers in your listening room.