Since I'd not swap glass beyond the two 300B Vinnie had included and certainly not tube types, I asked for bread crumbs. "If one rolled in something like the SV811, Elrog 300B and to some degree the KR PX4, the sound gets thicker and more saturated especially with the SV811. The TAK TA-300B is heavenly for those who love attributes like speed, resolution, articulation, spaciousness and air. Yes, fragile as well but I suspect this to change a bit with different amplifiers and speakers."

With DAC and phono modules installed.

On how L2 differs functionally from LIO or mirrors it for those considering to upgrade, "display off mode keeps the display off even when changing volume as you mentioned. Tube warm-up after turn-on is faster, around 20s vs 45s. The volume setting is saved and recalled when you power back up after L2 goes out of mute. With DAC and phono boards installed, there are still display modes for DAC USB signal sample rate and phono cartridge load values. L2 adds the mute switch to the front panel which LIO only has on the remote. L2's front trigger button turns on two 12V trigger ports to remotely power up external components like two L2 monos. The balance control on the remote still gives 12 x 1dB steps to the left or right without adding circuitry in the signal path. We just offset the stepped attenuator relay settings.  All of the L2 control circuitry is on the front panel and the bottom side (layer 4) of the motherboard running on a dedicated linear-regulated 5V tap off a transformer.

"The internal mains cable is shielded and only goes to the front panel PCB so no AC voltage passes through the motherboard. Both shielded power supplies are internally Belleson super regulated and the supply feeds to the DHT cathodes have a soft start to maximize tube life beyond running the DHT output with considerably less current than driving speakers. I love that when you look at L2 from the outside or with the top off, it is very clean and simple as are the front panel and remote. Yet behind it all, there were so many challenges to address."

Variation #1. Having by then concluded the SR1a review, I'd wrapped it up with the bow of this L2/Liszt combo. With 1MHz bandwidth, DC coupling to avoid signal-path capacitors, front-to-back balanced circuitry and class A/B lateral Exicon Mosfets, LinnenberG's are our resident take on Vinnie's own L2 monos. Hence they proved to be ideal implementers for his concept of setting your sonic course with the big triodes whilst the transistors merely amplify that flavor in the current domain to control and drive these radical off-ear ribbons. This became a truly spectacular showing and the best I'd heard any headphones perform. As floating open baffles, the Raal suffer zero ear-muff syndrome of compressed air, resonance and reflections from ear cups plus sweaty ears. Wings turned out ~30° makes for big lateral soundstaging whilst Aleksandar Radisavljevic's transformer-less ribbon tech presents zero energy storage for top speed, clarity, extension and very exuberant dynamic scaling.

The step response seems rather brilliant. Likewise for low THD+ IM distortion. The upshot of this special grouping of attributes and undeniable strengths is a tendency to brightness. As experiments with resistively shelving the +1.4kHz response showed which in default mode is perfectly flat, this perception of brightness is not a function of the amplitude domain. It's caused by raw speed in general, by unusual dynamic power in the upper registers in particular. Our ears simply aren't used to such unfettered reflexes and directness from conventional transducers and tweeters; especially not at 1cm from the ear canal. Here the L2's take became perfect counter ploy to mellow transient prickliness whilst its own resolution and bandwidth magnified the ribbons' unusually keen separation and micro-detail powers.

As Vinnie had predicted, swapping amps from no-feedback low-power triode types (albeit executed with transistors) to our class A/B high-power balanced amps with far lower THD changed the 'fragile' and 'floating' aspects into something more robust and grounded. The big deal here was to enjoy intense resolution at the same time as that more elegiac unhurried movement through time; what I think of as music's gait or attitude. We might call this tubular relaxation and elegance plus transistorized speed and resolving power in a perfect tango, no toes stepped on. Whilst gloss-white Nenuphar were still in place, I capriced upon the notion of driving them with a 15wpc Bakoon AMP-12R fronted by the L2. The amp from designer Akira Nagai works in the current domain for extreme bandwidth and again uses Exicon lateral Mosfets in its output stage. In most ways, it's a miniature Liszt. But its ~2Ω output impedance is ideal for the high self damping of these widebanders where the Liszt would overdamp them, never mind be seriously overpowered.