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Moving along to my listening notes, it quickly became obvious that the SM-300B needed a little time to settle and break in. It wasn't a lengthy process but I'd say a dozen full heat to cold cycles and 24 hours of playback seemed to do the trick completely. Initially the amplifier sounded heavy and slow but it opened up nicely once seasoned. I started the review with my usual system and connected the amplifier between the Burson Conductor used as DAC through its fixed outputs and the Calliope speakers, all cables being Ocellia Reference. Since the SM-300B offers a grounding post I also connected the Calliopes' static electricity drain to the amplifier (see my review of the Calliopes for more details on that feature). Once break-in was complete it became quickly obvious that Sasa Cokic went for a full expression of the 300B aesthetic with superb midrange centeredness at the relative expense of the frequency extremes; with superb decays at the expense of transients; and with bigger-than-life imaging at the expense of absolute accuracy. The SM-300B is certainly not an honest amplifier like you would say it about the FirstWatt F5 or J2. Even so its microdynamic capabilities in the midrange were simply stellar and like no solid-state amplifier I've heard. Here it played in the same league as Ocellia's 300B integrated. In a nutshell the SM-300B is a concentrate of everything that makes triodes love 'em or hate 'em but this affair was executed with the benefit of a master transformer designer.


Many tube amp designers look for ways to overcome the limits of the 300B either through massive very costly silver transformers like Ocellia or Audio Note; or with push-pull circuits as here chosen by Trafomatic. The concomitant power increase from typically 8 to 22 watts makes such an amplifier more friendly to a wider range of speakers and does give somewhat better control and dynamics. The Calliopes I started with are amazing speakers. Like few others they approach natural sound at least on smaller jazz and classical ensembles as that's what they have been designed to do. They are also proving to be many an amplifier's downfall by requiring little gain but having a very narrow operating spot for bass quality. Too much damping and the bass becomes dry and lifeless. Not enough as will be the case with most SET amps and the bass gets woolly and loose. Hit the sweet spot with a FirstWatt F5 or Triode Lab EL844TT and the result is powerful rich bass reasonably well defined.


With the SM-300B two things became immediately obvious. One, there was more limited treble energy than with my other amplifiers. Thankfully the Calliopes have variable-level tweeters since more often than not they will get paired with 300B SETs which don't mind a little help in the upper octaves. This gap was thus manageable for me but remains a consideration. Listening to Rostropovich directing Shostakovitch's 11th Symphony which ends in a mayhem of percussion, bells and cymbals, those cymbals lacked air and sparkle compared to my references. On the other hand the bells which are actually large darker-sounding bronze behemoths sounded truly amazing and bigger than I ever heard them. If I were to bet, I'd say their range lands them right in the sweet spot of a mezzo soprano as I heard the same magnifying effect with many a mezzo voice but more on that later.

The second thing this symphony revealed was the relative lack of bass transients. Kettle drum hits sounded like their mallets had been packed in wool. The resultant sound was big and bold but the initial impact lacked conviction. This surprised me as violins had bite, not to the level of the FirstWatt but enough to sound credible if not on edge as they should in this piece. I explored this puzzling behaviour through an extended comparison of guitar pieces, string pizzicato and various Japanese and North African percussion tracks.


The SM-300B played the same way over and over. It limited out on low percussion and bass transients but then showed far more attack energy and pizzazz on higher strings. Every time I put back the little Canadian EL84 push-pull integrated percussion impacts became sharper but showed less follow-through on mass. As a 6-watter the Triode Lab is no thunder giant but with a push-pull pair of EL84 the tube of little fame run under reduced triode power showed more authority and physicality on percussion albeit without the full expansion in time and space the SM300B was capable of on such notes.

It took a while to get used to the SM300B's somewhat schizophrenic transient behavior. It wasn't bad per se and made more sense once I learnt that Sasa listens to it primarily with Rethm Maarga [right] with active bass. It's thus something to be aware of as it won't suit all speaker types and listeners. It can be addressed with a DAC like Metrum's Hex which excels at lightning-fast transients far ahead of my Burson. That said, tables turned completely when I listened to voices or brass. The EL84TT is good, the SM-300B was magic. Of course one must be comfortable with a somewhat embellished presentation. The voices of soloists can suddenly appear magnified and perspectives be altered almost as though looking through a fish-eye lens. The soloist in front of you gets bigger than life, the orchestra beyond is pushed back farther into the background. This kind of presentation will drive measurement freaks crazy but send most opera lovers into a swoon. I loved it!


As the weeks went by I kept going back to my own schizophrenia. Beneath my reviewer hat I could hear the weaknesses of the Trafomatic amplifier at both extremes. But if I stopped long enough to actually listening to the music, I enjoyed it in a way I had not in a long time. There was no fatigue, voices were thrilling, piano notes floated surreally in huge recorded spaces and all these artefacts we should not care about converged into a beautiful experience. The SM-300B delivered full-on triode immersion. You just know it's too good to be completely true. But then you frankly don't give a damn because the music grabs you and just won't let go.