In case of the Triode Lab 2A3i, you can scratch my generic description of a 2A3. Instead envision a quick sure-footed amplifier with an open midrange, sweet treble, strikingly tight and fast bass and nice holographic qualities without succumbing to excess. As you'd expect, the 2A3i also excels at instrumental textures and spacialization with ebb and flow if not to the ultimate level of the 45-based Yamamoto A08s. Now that I described what the 2A3i can be, let me put it into context. To get to that level requires a fully burnt-in amplifier and tubes. The first hundred hours sound more dynamically constrained and bass output is truncated compared to what it will settle down to in the end.

Overall there is a point around that 100hr mark where somebody removes the parking brake and the 2A3i kicks into full gear. Up to that point it is good, just not jaw-droppingly good. When in full swing, it amazes. The second and pricey caveat is that you must upgrade from the stock JJ which are great for clocking burn-in hours on the circuit, to Czech Emission Labs which sound nothing like the stock tubes. They are punchier, faster, deeper, richer and more resolved; in other words, in a different league entirely. Depending on the model you settle on, mesh or solid plate, it will cost you $500 to $700 for the upgrade but you won't hear the 2A3i at its full potential unless you do, period. I note that Srajan too secured a pair for his Lio DHT assignment and described very similar improvements although seemingly to a lesser degree than I. You can probably blame that on the fact that the gold-pin electroharmonix 2A3 stock tube in the Lio is an already better tube than the Slovak JJ in the 2A3i to start with. Just as importantly, tube differences are amplified when the 2A3 bottle is used to drive speakers rather than an amplifier's input stage. The increased current capabilities of the Emission Labs are far more critical during speaker-drive duties than they are in a direct-heated preamp.

Finally and most importantly, to appreciate what such an amp is capable of, you will need speakers that thrive on SET power. Sadly that's far more complex and less predictive than simply going with high efficiency. Case in point, I currently run three sets of generally SET-friendly speakers yet only one truly shows its full potential with triodes. The Zu Essence and Finalé Vivace Mini sound excellent when paired with the 2A3i but shine even brighter when associated with a FirstWatt F5 for example. The F5 is probably the most piquant FirstWatt amplifier and both speakers benefit from that slight reinforcement in the upper ranges. They also both benefit tremendously from the tighter faster bass the F5 generates. Despite radically different technologies and design briefs, both speakers share a lot in terms of sonic profile. Both can get a bit boomy when paired with a SET even on the 8Ω output. It was no different with the 2A3i which on them sounded more like a good 300B rather than an excellent 211. I will elaborate in more details in the Finalé review but to my surprise, as good as it was with tubes, this small speaker was really made for low-power solid state amplifiers like the Zu.

However… when pairing the Ocellia with the 2A3i, one of those magical synergies happened as long as I took care of using the 16Ω tap. I had the same experience with all tube amps that came through earlier. Into this load, their 8Ω output lost control in the bass and things slowed down while overwhelming the pure midrange the Ocellia are capable of and known for. When on the 16Ω terminals, the perfect blend of drive and damping happened to deliver tight and punchy bass within the 45Hz capabilities of the speaker, with a pristine and highly resolved midrange and crystalline yet sweet treble. My guess is to expect similar synergy with other speakers designed to be at their best with triodes. Again, this goes beyond efficiency to include impedance and mechanical behaviour that must correspond to the low damping a SET will deliver. I would look at speakers from Audio Note, Rethm, Ocellia and Voxativ and others like them. Srajan of late mused about the vital balance between inner tension which respects the energy of the music; and comfort where each of us go for a slightly different mix. In my experience, we all note when things slow down to be a buzz kill or get so edgy as to drive us out of the room.

The Ocellia sound fine with the FirstWatt F5 but never fully get out of the first two or three gears to reach their full scale and dynamic capability. Of the amps I've tried, these speakers sound smaller and less deep on a solid-state diet. At the opposite end, all push-pull tubes I sampled, including the excellent Triode Lab EL84TT, still slow things down even when they get the scale right. Without fail, all 300B SET that came through were utterly incapable of keeping the bass under control. It bloomed into the midrange for a warm but boring sound and mushy low end. The 2A3i hit on all those hot buttons. It was fast, big and hit dynamic contrasts hard whilst also giving a highly resolved midrange and letting the whole musical scenery expand in all directions. Most striking with this amplifier was that the Ocellia delivered the best bass I heard from them, ever. The bass went low but was also tight and punchy when needed. It's about electro-mechanical matching, so-called synergy. When it happens, it's like magic. The beauty of a boutique outfit like Triode Lab is that they will work with you to hit that magic spot with your own speakers and whatever their unique requirements might be. To be clear though, even this amplifier couldn't redesign the Ocellia to become bass junkies. 45Hz is about all you get but in the world of SET and non-assisted widebanders, fast and tight 45Hz cycles are about as rare as hen's teeth.