I had the chance to visit Linear Tube Audio this afternoon and listen to the M3 Sapphires and three LTA amps. It was a real pleasure, and I thought I would share my impressions of the LTA amps and the M3s. I didn’t really think I would be writing up my thoughts on the visit, but it was so much fun I figured I would.
At the outset I would like to thank Nicholas of LTA for being so friendly, knowledgeable, and accommodating. He gave me a tour of the workshop behind the listening room, where everything is made and tested, and he was very kind to move cables back and forth so that I could compare amps easily.
First, the M3 Sapphires. I have a pair on order, coming likely in early August, and this was the first time that I had heard them in person. I currently have Harbeth 30.1 35th anniversary speakers, for reference. Three things struck me about the M3s.
One, they disappear. The room at LTA is not huge (14x12, I think.). The speakers were about 3 ½ feet out from the front wall, not way out into the room like on the New Record Day reviews on YouTube where Wilt Chamberlain could stretch out and take a nap behind them. The right speaker was about four feet from the shop’s bay window, with a curtain in front, looking out onto the sidewalk. There were some 2-3” thick panels on the front and rear walls and a ~6” panel on the floor on the front wall behind the speakers. The floor has an area rug on it, and seating is 7-8 feet from the speakers (which are 7-8 feet apart). All of which is to say that the M3s disappeared in a medium sized room without a studio engineer installing a complex mixture of room treatments. There’s nothing surprising about that given the design objectives of the M3s, but it was a lot of fun to hear it in action.
Two, they don’t punish you for being out of the sweet spot. The smooth and linear off-axis vertical and horizontal response and the bi-polar open baffle bass do the job. I moved from the sweet spot to a seat in front of the speaker on the right, and it was not yelling at me saying “I’m a loudspeaker.” The soundstage and holographic depth were not fully there, but the presentation did not collapse into one object emitting sound. There was still a larger field of music out in space, so for all the times when a glass of single malt by candlelight in the dialed-in comfy chair isn’t possible, the M3s still create a version of a sound stage in empty space. This is a fun and welcome benefit of open baffle and Spatial’s engineering of it.
Three, they inspire trust. The sound is coherent from bass to treble, tonally accurate, with a deep and wide soundstage, and I didn’t for a moment think that the M3s were interfering with what I was hearing or intruding themselves into the recording. This was a profound sensation. I’ve never listened to music without, at some level in the back of my mind, tracking one thing or another that the speaker might be doing to the sound. With the M3s I had the confident impression that they were fully capable of reproducing everything they were fed, from the texture and tone of the lowest bass up to the finest treble, and they were simply re-creating the music recorded.
The M3s made the LTA amps easy to compare.
We listened to three LTA integrated amps: the Z10, the Ultralinear, and the Z40 Reference—all current-production versions. Again, these were the integrated amp versions with remote controlled ladder resistor-based volume controls (click, click, click) in each. Nicholas had a dB meter on the table by the listening chair so I could tweak the volume after he switched amps to minimize any differences due to loudness.
The Z10. The Z10 sounded excellent, but both the Z40 and Ultralinear amps provided a bit more detail and separation. I spent the rest of the time comparing the Z40 and Ultralinear. That’s not at all a criticism of the Z10, but hearing a side-by-side improvement I wanted to zero in on whether I preferred the Z40 or the Ultralinear as an upgrade from my Benchmark AHB2 once the M3s break in.
I listened to a selection of music files that I brought, played through the Lampizator DAC (not sure which flavor, but it’s huge and has a big bottle tube sticking up in the middle) controlled via Roon on a tablet. The music was classical (orchestral and piano), jazz, New Orleans R&B, and live rock. I brought a variety that I’m familiar with and listen to regularly, including a few things that always sound off or problematic to me.
The Ultralinear compared to the Z40 Reference. For my ears, with the music I brought, in the LTA room, I settled on the Z40 Reference. A couple of things led me to that conclusion. First, on an orchestral piece the Z40 placed an oboe in the orchestra very precisely and with natural tone. There was an oboe in one point in space, sounding like an oboe. The Ultralinear presented the same oboe to me (which is down in the mix and not obvious) with a bit of a “golden glow” around it and not as precisely placed in the orchestra pit. These are subtle differences, but I was looking to make a choice.
Nicholas accommodated me in switching back and forth for several tracks. Another thing that tipped my preference towards the Z40 was vocals. On Mother Nature’s Son from the White Album, the Z40 let me hear a bit more of the subtle complexity of the vocal—it gave me the impression that I could see Paul McCartney purse his lips to make an ohhh sound. This is the kind of thing that sounds nonsensical in audio reviews, but still it’s the impression I had.
Going back and forth I found myself forgetting the equipment and listening to the music with the Z40, and with the Ultralinear I was more frequently listening for the slight prettying bloom that it imparted here and there.
As a match to the M30s in a small-medium room, the Z40 seemed ideal, but I could see the Ultralinear being someone else’s first choice, maybe with the X3s in a larger room where the subtle way the amp brings things a bit forward (not in a bad way) and gives just the slightest bit of color to things might really work well in the larger space. It’s clear why LTA would make two amps at the top of their range.
LTA is handmaking amps with care, and my trip to their place made it clear why they’ve been working with Spatial Audio Lab. When the M3s settle in, I expect I will be getting in touch with Nicholas about the Z40.
Happy listening!
