The LTA UL Integrated arrived a week early. Here are some thoughts regarding how it stacks up against my XA25/EAR868 pairing.
I was surprised by two things:
1) The LTA has more and fatter bass than the XA25.
2) I preferred listening to the LTA at lower volume than the XA25, which makes me wonder if the LTA’s frequency response is, well, more linear. I do need to push the LTA a bit though, volume was between 60 and 67 for the session, which tells me that the Spatials’ sensitivity, combined with the 4 ohm impedance, is borderline too low.
The XA25 is more dynamic but only by a hair. Both are very detailed but I was surprised by how detailed the LTA was given the tubes. Music seems to flow and pulse from the LTA, like it has a beating heart. The XA25 is more neutral, a tad less euphonic. LTA soundstage is wiiide, even bigger than the XA25, which is no slouch. Overall, the LTA envelopes you in sound, like being wrapped in a warm blanket!
Other observations: the LTA gets pretty hot! I guess that’s tube amps for you. I have it on a separate rack with nothing above it so all good. It’s so light. Lack of output transformers along with the switching power supply? And it is unbelievably quiet, which I stack up to good engineering along with the ZOTL topology. I’d love to try the amp with uber-sensitive speakers in the 8 ohm, 100 db range (i.e. horns.)
Is the XA25 leaving the stable? No. I won’t sell it since I don’t know what speakers are in my future and the amp could be the perfect fit for the right type of speakers. But the LTA is a revelation. As long as it stays comfortable with the volume at 60%, it’s all good. Admittedly I am wondering if the Z40 may be the better fit for the Spatials (because of the higher power output) but then I would probably lose some of the glorious detail and bass the UL seemingly magically pulls off.
Overall, I'm extremely impressed. That's a lot of performance packed into a smallish, light package.