Listening to VTL’s latest, the Lohengrin mono-blocs
By Dennis Davis
One of the most highly anticipated new components of 2025 was VTL’s new, more compact, mono-bloc addition to their Reference Series. First seen in development guise at Munich in 2024, the finalized version was expected to launch at the 2025 Hi End Show, but although the circuit was finished, the company was yet to finalize a new aesthetic, meaning that the units playing in the room looked exactly like the established Siegfrieds – being built into the same casework. Casual listeners may have wandered into the room and turned about thinking “nothing new here.” Which just goes to show how dumb it is listening with your eyes: even a brief listen with your ears should/would have told you there was something a little special happening in that room, a room that garnered universally positive commentary from the press. Proper casework wasn’t the only thing the new amp lacked, so perhaps it’s only fitting that, as per the legend, when the name was finally revealed, it should be Lohengrin.
It wasn’t until the end of last year that VTL received the final casework, fit all the bits into their more compact space, ready to begin shipping the new amplifier to dealers in the first week of the new year. Finally available, a pair of Lohengrins retails for $100,000.
Although it shares more than a few styling cues, a control panel and casework components with the existing Siegfried and S-400 Series II models, the Lohengrin is, unmistakably a “New Look” for VTL. It’s like they put Siegfried on a diet. The casework has been downsized, along with the footprint and the amp measures 11.5” wide by 19.25” deep by 19.5” high. That’s the same width as the flagship amps, but it’s almost five-inches shorter in both height and depth, making the Lohengrin a whole lot easier to accommodate. But, styling-wise, the big shift is the addition of a window to the front of the case, exposing the vacuum tubes to view, rather than concealing them.
Meanwhile, the real changes are inside the new casework. The new amplifier incorporates the same driver stage, fully regulated power supply and power transformer as the Siegfried Series II amplifier, as well as the more advanced fault sensing circuitry from the 450 Series III mono-blocs. As you can see from the side-view of the open chassis, fitting all that circuitry into a significantly smaller volume has required packing puzzle precision. A heatsink off the rear of the unit, requiring 3” clearance, does its job without interfering with the aesthetics of the unit from the listening position.
The Lohengrin’s output stage uses eight KT88 tubes per side, sourced from JJ Electronic in the Slovak Republic, to produce 400 watts into an 8Ω load. Although VTL used 6550s for many years, and those output tubes remain an option, I for one prefer the sound of the KT88 in VTLs amps and these days, that is how most of them are shipped. So far, window aside, so predictable – so where does that step up in musical performance come from? There are certainly revisions and refinements to the circuit topology, but Luke Manley believes that the biggest factor in the Lohengrin’s exceptional sound is its newly designed output transformer, with significantly more sophisticated interleaving of its windings.
