In the end I alighted on the 2A3 as the most balanced jack of all triode trades. Its 3.5 watts were just sufficient to energize the Ocellia, its upper midrange liquid enough to deliver a good dose of vocal magic without ever matching the 45, its bass low enough to provide body and warmth without ever reaching as deep as the 211 but without the slop of the 300B either. The 2A3 often ends up being the ugly duckling amongst triode cognoscenti. It's not as good as the more well-known triodes across their respective areas of strength. I simply have always found it to be the most balanced triode, its shortcomings being more small omissions than egregious offenses. My Triode Lab integrated with its custom output transformers hand-picked to match the Ocellia has given me thousands of blissful hours. Over time I simply observed that I tended to restrict my listening to the types of music the system handled best. No more Gorillaz, U2 or Mahler symphonies. It's not that I made a conscious decision to keep such fare off my playlists. It was a more insidious erosion whereby challenging tracks showed up less and less because they just didn't feel alive. It took me a while to understand that it wasn't due to recording quality but what I've come to term triode fuzz. It's a slight blurring of transients that always translates to less than lifelike dynamics and an inability to cast sharply defined images.

Triode fuzz is also why poorer recordings can sound much better through SET. Those recordings often lack the dynamic contrast and resolution that triodes would mask in the first place whilst triodes can offset threadbare or bright tonal imbalances. My past few months thus have been a journey to find a transistor amp that would retain what I love about triodes whilst minimizing their faults. And I actually found it and more but it did take trial 'n' error. My first try and biggest mismatch was the mighty Pass Lab INT25. Pure class A, low wattage, warm and with plenty of resolution and cavernous bass, I felt like this was going to be instant bliss. I couldn't have been more wrong. Although the Pass doesn't have a huge damping factor by transistor standards, its grip on the drivers was such that they completely shut down to flat and joyless. The sound was warm, resolved and had deep bass but the music didn't breathe. Continuing with Pass I went 0:2 after borrowing a friend's SIT-3 and Pass XP-12 preamplifier. Of all the amplifiers I tried it was the most triode-like for warmth and 3D imaging but actually too triode-like. I didn't hear the gains in dynamics I was looking for and the amp struggled with very dense music much like my 2A3 integrated. I was looking for better, not a lateral move. I've since read that the SIT amps do much better into 8Ω loads and Zu provide resistors that can be strapped across binding posts to lower impedance and improve compatibility with SIT amps. Without that tweak, the SIT3 was a very fine amp but not sufficiently superior to justify the cost of changing over.

When Musical Fidelity relaunched the original A1 with a few part upgrades aimed at improving reliability which was relatively poor on the original, I decided to reconnect with an amplifier I enjoyed very much decades ago. The A1 now sells for $1'700 but despite being a fifth of the Pass INT25 delivers the 'same' pure class A 25wpc. The combination with the Ocellia couldn't have sounded more different. The A1 offered solid bass without the iron-fisted control of the Pass and musicality returned as if the speakers were breathing again. The A1 is a very expressive dynamic lovable amplifier with the famous British PRaT in spades so I knew I was getting closer. But it's also fairly coloured and far less resolved than other amplifiers I tried, especially in the treble which lacked sparkle and air. There was a lot to love especially with my good-ol' Rogers LS 3/5a that don't do sparkle and air in the first place. I simply really love a midrange-centric energy bundle of an amp. The Rogers and A1 were a match made in heaven but the Ocellia showcased the shortcomings of the affordable amplifier too much so back to the distributor it went. I tried to secure a Sugden A21se which by all accounts should have been a good match but wasn't successful. Then an Enleum AMP-23R arrived and I stopped searching. Out of the box that was it and things only got better after a few hundred hours of play. Let's start with the unexpected. The Enleum's midrange is as fluid, organic and intensely lifelike as my 2A3 SET. Compared to a great 300B, singers aren't quite as large and 3D between the speakers but vocals have resolution and inner light with just a touch of sweetness that's addictive. Because the AMP-23R operates with much lower noise than any SET I ever heard, the little bit it loses in vocal 'zoom' it more than makes up for by letting singers float against a darker background. That provides more separation from the surrounding instruments. Separation can become a negative when multiple artists sound disconnected from the whole but not here. What I get instead is less confusion. If you're a visual listener who thrives on nicely defined images, the Enleum delivers aplenty.

Things get even better as one travels down the frequency range. The lower midrange and upper bass gain weight, definition and impact. The power zone of the music becomes physical. For years I assumed that Ocellia couldn't do percussive impact. Not only can they, they do so with superb speed and transients, not quite like Zu but much closer than ever expected. That speed, resolution and clean transient timing continues all the way into the mid 40s where the Ocellia eventually call it quits. But bass is where the Enleum truly breaks away from triodes, providing much cleaner imaging, greater separation and textures than you would get from even the best 211. It's mind-altering to hear that kind of performance from a widebander, even more cognitively dissonant from a puny box hardly bigger than my Denafrips Pontus DAC. Of course the Enleum forgoes all hint of triode fuzz. In fact it's the antithesis of fuzziness with a superb sense of timing and lifelike dynamics. If emotions and contrast are part of a recording, the AMP-23R will convey them unfiltered so raw in the best sense of the term – unedited. That was probably the most fulfilling revelation. It allowed the Ocellia to show their true potential. I'd never allowed them to fully get out of first gear with the other amps I tried but finally given permission to do so, they got unleashed to serve the musicians' intent. Many transistor amplifiers are tagged with that ability, from Gryphon to D'Agostino to Boulder, but the Enleum does it without a hint of harshness, with saturated tone colours and a holographic liquidity which big muscle amps often can't touch. The Enleum doesn't editorialize poor recording. If they're hot, they'll render as such. But it doesn't emphasize recorded shortcomings either. It's that unique combination of traits that has me declare the Enleum AMP-23R the best triode amplifier I ever heard so with most of their beauty and none of their flaws.

If we want to pick nits, there are a few things to mention but all are dwarfed by the sonic qualities. First and foremost is the small form factor and light weight. As great as this may seem, thick rigid cables become a challenge as they will often tip the amplifier unless you load it with a heavy weight. Because of the tiny form factor, we only get two RCA inputs and one proprietary current-mode BNC for future Enleum DACs and phono preamplifiers. No XLR, just 2 usable RCA inputs and no variable outputs to connect subwoofers, the Enleum is beautiful in a very minimalist way and the feature set equally minimal. The AMP-23R has been broadly reviewed and praised as a headfi champ. It's also collected many accolades as one of the most affordable entry points into very high-end performance for speakers presenting reasonable loads and sensitivity. Yet no review I saw pegged it face to face with SET and for me that was a revelation. The Enleum truly highlights the limitations of triodes in microdynamic, transient and timing realism, silence of operation, bass depth and resolution but does all that without giving up on triode liquidity and imaging. Until now I considered FirstWatts' SIT amplifiers the only viable transistor alternative to SET for my speakers without fully reaching the dynamic prowess or transient accuracy of the very best transistor amplifiers. The Enleum does both and is in my view the best option for triode lovers looking to improve their system. Considering that the AMP-23R costs a fraction of the very best 300B, 211 and 2A3 integrateds though isn't itself cheap by any means, it certainly is a fantastic value and an incredible headphone amplifier as well.