Parallel apartheid. Vocal or instrumental single or dual octave doubling duplicates the effect of 2nd and 4th-harmonic THD. It's an enriching quality for which at the correct dosage no-feedback direct-heated SET amps are popular. On this short track from Eda Karaytug's Gönülden, male and female voices, violin and qanun all play the same melody separated by octaves. That creates a compound timbre in a downtempo tune of courtly Ottoman airs. Our attention can fix on the deeply layered timbre as one construct; or attempt to track all individual contributors in parallel like a fugue. To perform such separation in real time not only takes concentration—we're riding multiple tracks at once—but a system refined enough to allow for such separation. With the AMP-54R, mine did. If our listening habits don't do this peeling to leave the onion whole, such hardware knife skills are redundant. Given how many reviewers restrict their sonic descriptions to bass, midrange, treble and soundstaging, it seems that tone modulations of harmonic shifts, timbre stacking, venue overlays and other aspects are of less or no interest. How many people still enjoy large choral works particularly from the sacred Russian repertoire? As with massed strings, grouped voices present their own playback challenges. Once served, those can lead to discoveries which enter different territory than hard-hitting techno, pulsing Reggae or compressed Pop. Many of this amp's more impressive aspects reveal at job sites not everyone visits. For that my running subtext word has been 'advanced'. This really is an advanced machine for advanced listeners. Is that a racist statement? Is any superiority involved even implied to say that if we don't eat fried foods, our home kitchen won't need a deep fryer? I call it money saved, messy clean-ups, dead-oil recycling and splash burns avoided. Pop music offers other parallel tracking ops. Remembering two sunny years in Paphos/Cyprus, I spun up 2003 Giannis Parios whose voice then still had full power. On the melody's recurring peaks when the harmony singers enter, can you tell how many there are and where?

By simple cash count, we know that the AMP-54R won't win popularity contests to sell Grammy-kind volumes. It pursues a niche audience. Hence my attempts to imagine what type of listening such an audience might apply to make for a good match between needs, expectations and deliverance. To imagine the ideal target audience is one of a reviewer's tasks. My imaginary—imaginative?—crew might try to peel this six-handed musical onion from a fantastic Jacques Loussier album called Take Bach where he plays with Turkey's Pekinel sisters by way of a J.S. Bach transcription for three pianos with Jazz upright and drum set. It has the playing styles alternate between legato and highly percussive, the latter making demands on transient precision atop tone-wood resonances. As my meandering examples hoped to illustrate, the AMP-54R allows observant listening. Here we don't merely follow a tune like a sleepy passenger rides a train controlled by someone else. We investigate structural elements, observe artistic accents on texture/timbre shifts, hear simultaneous events clearly separated if we wish, sense ourselves occupying a different place than the one we're in; and more. If we walk this assessment back to its beginning to see its enabler, the catch-all 'resolution' term could acquire deeper meaning. There are many more facets to resolve than generic detail like a squeaky chair, woodwind's key clack or guitar's finger slide.

What empowers such multi-faceted resolution? What is detail to begin with? How to know our system's quality if we never play stuff to challenge it? These are good questions to ponder. As a mental exercise they'll clarify what the AMP-54R can do; how so; and whether it'd suit your temperament and listening mode. Is yours investigative, critical or more passive? Is it physical—bopping head, tapping feet, air guitar—or self-forgetful like a day dream that leads to mildly altered states? By implication, qualities I haven't mentioned weren't absent as though other shelves of the Enleum store were empty. They simply didn't step forward. At right there's a tribute to all the youths around the globe who dedicate themselves to becoming musicians. This is a famous Azeri song of which I've heard multiple takes. This is my favourite. Wait for the thrilling climax. Did this young man win a competition? His country's president nearly cried when he hit those high notes.

At left there's a track for fans of violins who can't handle Beethoven's quartets or even Vivaldi's Four Seasons; plus one for friends of the cello albeit in unexpected places. All sugar then, no almond bitters?

No system can do all music styles equal justice. That's my conclusion after 20-plus years on the beat. If we want maximum lucidity, music supposed to sound grungy will feel dry-cleaned and starched. The bottom-up balance and ballooned imaging of amplified live music conflicts directly with the top-down balance and sharp focus of small-scale acoustic chamber music. The list of contradictory demands is lengthy. Much modern music wants bass extension and control that could overdamp the resonant qualities of an upright Jazz bass. If we love our system on stadium Rock, it could make a Baroque period ensemble sound terribly wrong. Many of these opposition demands don't blend nearly as neatly as Niño Josele's inspired mix of Spanish and Berber idioms. Before my report suggests a 'perfect' amp, consider my pick of music examples – and terrain I didn't cover. Whilst 100 watts are a new exchange rate in Enleum currency, three times more power off dual 800VA power toroids as in my Dazzle does different things. Even if we don't scale up to grand orchestral, the dynamic range embedded in premium productions of rather smaller ensembles still unfurls more. If we want a warm humid tropical sound, this won't be it. Neither is it dark, nocturnal or particularly thick and chunky. Some of it could be injected with a deliberately seasoned preamp. Chances are, if you part with 25G on what functions like an integrated, you may not be prepared to. If your majority music library is of middling quality though you adore the music, the true abilities of the AMP-54R could either remain untapped or reveal things which ignorance kindly shielded you from. The keys to a Porsche don't belong in the hands of a testosterone-crazed 16-year old.