Designer Massimo Costa rates it an honest 85dB (2.83V/1m). Thus our Albedo Aptica in this space's bigger cubic volume with higher ceiling came fully alive at 60 on the dial. I had throwaway gain to hurt our ears again. This gives you a good read on what type speaker you can drive with the Z10's seemingly marginal paper power. Once more, this is not about "louder" tube watts but sufficient voltage gain. With smaller albeit transmission-line loaded mid/woofers like Albedo's 1st-order Accuton, I heard nothing to suggest lack of control or compromised bass extension. Despite the apparently poor fit on specs, this was a categorically great fit at the ears.
To reiterate and segue into this review's final straightaway, the Z10's special appeal is being mostly about very good transistor sound. Then it adds that fluffy airy cap of whipped cream on top. That injects more textural generosity. Its aroma, at least in my experience thus far, most resembles the 45/50 direct-heated no-feedback triode yet is, quelle horreur, squeezed from cheap EL84 pentodes. That's a major bonus come retube time. But when we're promised 10'000+ hours, that'll be a while. There's more. Everything about the sound applies 100% to headphones including today's toughest loads like HifiMan's Susvara. The Apple remote works a charm. The menu features are perfect. The capacitive-touch brass buttons will never break. Lacking big humming iron, the Z10 is a physical lightweight. Running its tubes smart not hard, it also doesn't get hot. No matter how I rotate my mental lazy Susan to spot any chinks in the armor, I don't see any. The proprietary Berning circuit inside is well proven and Linear Tube Audio's collab with Roby & Fern has elevated their simpler first chassis to being fully competitive with 2019 standards.
The perhaps most fitting way to shoehorn the Z10's sound into one sentence is to call it a triode preamp + fast wide-bandwidth class A/B direct-coupled transistor circuit in one box. That's what it sounds like, never mind its alien all-tube Zotl architecture. In our household, it's a Vinnie Rossi L2 Signature linestage run into a Bakoon, Crayon or LinnenberG amp, then scaled back a bit on dynamic range and soundstage scale but otherwise the same flavor or presentation style.
Just when you thought it couldn't get better, add factory-direct sales. Those knock off 50% of the usual markups. Elsewhere this would be a €10'000 machine. As we learnt, you can drive normal speakers with it, not just gentle tube loads. Combine all of it and see how the award pretty much wrote itself. I just followed along, dragged by an unbreakable leash of clear proof from very happy ears and critical reviewer eyes.