Gained voltage. Speaker sensitivities are all over the place. Not only do they differ, how they're derived does. So engineer Cees Ruijtenberg rates his Acelec Model One at 84dB—a realistic figure given his modest cubic volume with big bass—whilst Kroma rate their somewhat bigger Mimí an in-room 93dB. Yet when I'd earlier compared the two, one in each channel, the image stayed dead center. Both played equally loud, exactly. If the Dutch 84dB rating suggests borderline if not flat-lined proof of life on today's measly 10 watts, we need our measles shot. We must remember that it's not current but voltage gain which determines our final loudness. In my setup, the DAC's XLR delivered a max 16V. Atop that, the Z10's preamp/driver quartet of tubes preceding the EL84 in the output stage added their own 18dB of voltage gain. At 50 on the dial, the Acelec played the room. At the uncut 99 possible, at least the left box would have turned into a leaf blower.

In this ~4x6m space, nothing bigger than a good 2-way monitor is wanted. Here the Z10 is guaranteed to handle serious über monitors from Magico to Stenheim. If you rather book an Uber for a lower fare, the €5'400/pr Acelec belongs in the same aluminator club but in such elite company at least, shaves off significant coin. On attainable loudness, the Z10 gets audible at 01 out of the gate. It's not a silly design with actual decibel reading where the first 30-40dB above 0 hide inaudible below your room's ambient noise. This volume gets cooking right off, then its circuit has plenty of gain to well exceed what its 10-watt power figure might suggest. So a smaller Harbeth as a popular brand in the monitor genre should be just as copasetic as our Acelec and Kroma stand mounts. Time to hit the bigger time downstairs. Here I rigged up my closest approximation of Dan's rig: Soundaware D300Pro SD card transport ⇒ Denafrips Terminator R2R DAC via I²S over HDMI ⇒ Vinnie Rossi L2 Signature linestage with Elrog ER50 ⇒ the Berning in amp mode ⇒ Cube Audio's Nenuphar 10" widebanders.

Sometimes the best-laid plans don't get laid. Though Nenuphar is 'just' ~93dB—low for the breed where Rethm and Voxativ hit 98-100dB but higher than most multi-ways—the combo of L2/Z10 proved noisy. Unlike fuzzy thinkers who worry about ultrasonic noise reduction in digital but tolerate audible noise from valve gear, I consider noise at the speaker driver/s unacceptable in high-performance audio. The combo's sound also felt too slow. So running Z10 in HT mode got scrapped. Incidentally, configuring your input not only has the display confirm "input 2 is now home-theater" in the menu. Selecting input 2 thereafter replaces the standard volume readout with the letters HT. Only the blind or careless wouldn't know not to send full-blast signal to said input. It's a brilliantly effective use of a minimalist display.

Plan B compared L2/FirstWatt SIT1 to Z10. This put a dead-quiet 2-stage hybrid in one corner where direct-coupled DHT drove single-stage single-ended static induction transistors spread out over three chasiss. In the other corner was a 3-stage all-tube integrated which already played the room below 20 on its dial but still exhibited exactly the same level of mild noise as it had with the Vinnie Rossi. Lowering the circuit's standard gain with lower-gain input tubes might reduce or eliminate that low-level noise. I just had no such bottles on hand to know for sure. As it happened, the 10-watt power rating between my combatants was shared but on price, it was €28'000 (with boutique power triodes) against €5'000 so most skewed. That this wouldn't skewer the Berning sonically I already knew from its upstairs showing.

On gestalt in fact as that carefully curated feel or aroma which these particular direct-heated triodes impart on the proprietary Nelson Pass transistors, this was a perfect overlay. Where our resident far costlier 3-piece set played tribal elder was that its outer soundstage coordinates still moved outward and up to expand and get bigger; that dynamic contrast was higher with consequently higher peaks; and that the perception of effortless flow was stronger. But, if you didn't know the difference from a direct A/B, you'd be none the wiser and in the exact same bailiwick. My deliberate tuning with Elrog's modern 'super 45' triode was well reflected by the Z10's own voicing. That meant that it too emphasized speed and a lit-up presence/treble region over what Western Electric's or Elrog's own 300B do in the same Vinnie Rossi grounded-grid circuit. For tube-savvy listeners, that's a valid pointer. Think of the Z10 not as a 300B/2A3 but 45/50 clone super-imposed on about 80% transistor virtues relative to bandwidth, speed and linearity. Or call it a Bakoon or Crayon plus 20% of triode flair.