That segues back at perhaps the XA25's core attraction. Routinely the informative angle—high resolution, detail magnification—thins out raw physicality to push us right back into the observer position. We notice, count, dissect and appreciate but somewhat from a distance not that emotionally involved. In a quite unique way the XA25 managed to both go for the gusto and be particularly insightful and multi-hued with that special magic in the midband. I believe it's that cluster of qualities which had Terry London email that "I still cannot believe that I'm not listening to a great tube SET…" That reach-out-and-touch or illuminated-from-within factor is traditionally their forté. Not having a tube SET at hand, I can't know to what extent a premium example might still eclipse the XA25. But making that mental connection seems relevant.
With LinnenberG's Allegro and higher-power Liszt monos on hand, it was mandatory to press those into service. The upshot wasn't unexpected. As members of my 'Swiss' club, they were rather more explicit from the presence region on up; even quicker on the transient uptake; and more sorted, separated and organized in the usual matters of soundstage coordinates. This rotating of specific qualities into the foreground naturally meant that others moved further into the background. Those aspects included the XA25's fruitiness, earthiness and simultaneous projection power beyond that of even the XA-30.8. To quantify, it took the €15'000 Nagra Classic Preamp, a tightly engineered 12AU/AX7 tube deck with integral Swiss SMPS and -125dB S/N ratio, to generate XA25-level body, weightiness and moisture from the drier LinnenberG without eating into their resolution. Meanwhile the Pass managed with a €3'500 solid-state Wyred4Sound preamp admittedly of hot-rodded Stage II status so costly denuded Vishay resistors in its attenuator ladder. My trials with actual tubes if only small-signal sorts reiterated why existing commentary on the XA25 hasn't been able to avoid glowing glass comparisons. Though certainly only a partial overlap, it was demonstrable and far from imaginary with my deluxe Nagra review loaner.
Given the XA25's tech brief, we're left to consider these results less due to its beefy Ixys hockey-puck transistors and more what they eliminate: ballast resistors and that other form of feedback. If the XA25's unfair advantage over our XA-30.8 was mostly or just that, we might be curious how team Pass will eventually scale up that recipe to higher power. By March 2018, the majority of folks in the market for a premium stereo amp shouldn't have needed more power than the XA25 delivers. It nearly triples its spec into 1% THD to support momentary peaks well beyond the standard power envelope. That's a certain effrontery when in the established way of things, design advances trickle down from above. It's invariably a top or reference model which introduces a breakthrough. It's only later that revisions of lesser models inherit it; and then often not at the full dose to leave big spenders with some exclusive bragging rights.
With their most affordable stereo amplifier, Pass Labs stand that tradition on its head and make their entry-level buyers the very first and original beneficiaries. The XA25 introduces a tech advance which now must trickle up if its joy is to spread out. In the same downside-up but happy spirit, a prior Blue Moon award for the XA-30.8 demanded that the less costly but better than heel-snapping XA25 collect its own. Given its breakout performance and positioning, anything less would have been dishonest!
Postscript. To make this reboot more than it was originally, Dawid Grzyb in Warsaw received his own XA25 for HifiKnights in 2023. Here's the gist of his findings.
"Beyond Enleum's AMP-23R of 25wpc with adjustable gain disguised as volume control, I also dusted off my FirstWatt F7. The XA-25 behaved very much like its integrated Pass sibling had two years ago. Considering that the latter houses the former plus a passive linestage, that was hardly a surprise. The standalone amp had the same wonderfully complex personality. It sounded like a full-fledged class A type highly adaptive to the music on the menu. Some tracks revealed quickness and resolution, others prioritized tonal saturation and color. How we perceive sonics depends heavily on context. Here the F7 was a nice reminder on how quick, punchy, raw, resolved and radiant the XA-25 is. The FirstWatt was more distant, round, chunky, lazy, less controlling and slightly hollow in the bass. The smallest Pass was more illuminated, open, feisty and dug substantially deeper into my sound|kaos Vox 3awf monitors which felt more anchored. It was texturally fruitier so of higher saturation and wider color palette. It also presented images more strongly outlined and projected them closer to boost intimacy and directness. As polite upon demand and elegantly voiced as it was, the Pass was clearly the sportier, more intense, instantaneous and engaging of the two. Srajan described the F7 as passive by comparison. I couldn't agree more. The XA-25 was the substantially higher-tiered product. It had the upper hand on all fronts and impressed me far more. Its quicker, spatially more sorted, accurate, powerful, clear, vivid and intense demeanor marked a clear progression rather than simply different sonic perspective. It excelled at everything and sounded fantastic. It also behaved far more powerful than its specs suggest.
"During their skirmish the Pass and FirstWatt both connected to the costly and fully balanced Trilogy 915R preamp. Next came the half-priced and single-ended Thöress DFP geared for color and tonal mass while projecting images closer up. This perspective effectively bends the soundstage around the listener to elevate directness and closeness. My Vox monitors amplify that effect still more. Although tubed, the DFP makes highly agile, energetic and engaging sound. It's like an espresso not latte of wide color range, spatial complexity and heft. With the Thöress the XA25 produced sound that had me at the edge of my seat one way or the other. The outcome was pure intensity in each sense of the word: tone, image size, attack, detail retrieval, substance, power and excitement. The Pass was very pleased with its valved companion driver and so was I. I actually enjoyed it more than the Trilogy. This pairing showed how much more rapid and feisty the XA-25 could still get whilst maintaining its class A charms. In the conclusion of my earlier Pass Labs INT-25 review, I wrote that many amps would love to sound like it. Back then I wasn't aware of any that could. Now I know of the XA-25. It's visually utilitarian yet classy then built to last generations. It gets by perfectly with minimalist i/o, operates flawlessly and is perfectly silent without signal. It's noticeably more affordable than its integrated sibling yet as awesome where it matters most. If 25wpc are enough and you after a high-value stereo power amp, auditioning the XA-25 prior to anything else is my sincere recommendation. It's superb across the board and worth every penny."
Postscript 2. Which still wasn't the end of this story. Pass Labs instructed Dawid to forward his sample to me. With a new room, new speakers, new sub, new active xover, new DAC and new USB bridge since 2018, I had a whole new bag of old tricks to dig into. That features as a separate review.
