AMP-54R

Reviewer: Srajan Ebaen
Financial interests: click here
Main system: Sources: Retina 5K 27" iMac (i5, 256GB SSD, 40GB RAM, Sonoma 14), 4TB external SSD with Thunderbolt 3, Audirvana Studio, Qobuz Sublime, Singxer SU-6 USB bridge, LHY Audio SW-8 & SW-6 switch, Laiv Audio Harmony; Active filter: Lifesaver Audio Gradient Box 2; Power amplifiers: Kinki Studio EX-B7 monos & Gold Note monos on subwoofer; Headamp: Enleum AMP-23R; Phones: Raal 1995 Immanis; Loudspeakers: Qualio IQ [on loan] Cables: Kinki Studio Earth, Furutech; Power delivery: Vibex Granada/Alhambra on all source components, Vibex One 11R on amps, Furutech DPS-4.1 between wall and conditioners; Equipment rack: Artesanía Audio Exoteryc double-wide 3-tier with optional glass shelves, Exoteryc amp stands; Sundry accessories: Acoustic System resonators, LessLoss Firewall for loudspeakers, Furutech NCF Signal Boosters; Room: 6 x 8m with open door behind listening seat; Room treatment: 2 x PSI Audio AVAA C214 active bass traps
2nd system: Source: FiiO R7 into Soundaware D300Ref SD transport to COS Engineering D1; Preamp/filter: Lifesaver Audio Gradient Box 2; Amplifier: Kinki Studio EX-M7; Loudspeakers: MonAcoustic SuperMon Mini + Dynaudio S18 sub; Power delivery: Furutech GTO 2D NCF, Akiko Audio Corelli; Equipment rack: Hifistay Mythology Transform X-Frame [on extended loan]; Sundry accessories: Audioquest Fog Lifters; Furutech NFC Clear Lines; Room: ~3.5 x 8m
2nd headfi system: DAC: Cen.Grand DSDAX 1.0 Deluxe; Headamp: Cen.Grand Silver Fox; Headphones: Raal 1995 Magna, HifiMan Susvara
Desktop system: Source: HP Z230 work station Win10/64; USB bridge: Singxer SU-2; DAC: Sonnet Audio Pasithea; Head amp: Kinki Studio THR-1; Speaker amp: Crayon CFA-1.2; Speakers: Acelec Model One Headphones: Final D-8000
Upstairs headfi system: FiiO R7; Headphones: Meze 109 Pro, Fiio FT3
2-channel video system: Source: Oppo BDP-105; All-in-One: Gold Note IS-1000 Deluxe; Loudspeakers: Zu Soul VI; Subwoofer: Zu Submission; Power delivery: Furutech eTP-8, Room: ~6x4m
Review component retail: TBA

Leap. We could frog or faith it.

Ancient pond. Frog jumps in. Plop. Basho's famous haiku.

Modern UltraFi. Frog leaps out. Bling, pling. It's Enleum's AMP-54R.

It leaps two ways. It claims illustrious performance beyond the 25-watt AMP-23R. To sanctify many more speakers, it leapfrogs to 100 watts. It then embraces extremist visual finesse to celebrate thin-is-in futurism. It asks our leap of faith that the associated costs for such hyper styling are well spent other than b(r)agging the creators yet another Red Dot Design award. With beauty in the eye of the beholder and worth in her wallet, you be the judge. No argument, the projected €25'000 ask next to the soft transistor power rating seems beastly. But Enleum's founder Soo In Chae doesn't plot ordinary metal boxes. Nor does he subscribe to bigger is better. He practices Apple chic without the corporate leviathan's resources and Chinese labour. His is a low-volume Seoul boutique enterprise with a small San Jose design office. Just so, Soo In's design ambitions are clearly Cupertino. Just look at this floating flounder. Looking is free. Enough on expense. One can no more accept such a gig then later grouse over the cost of admission than groan that a steak house doesn't serve tofu burgers.

If today's super-posh terrain is still unfamiliar, do the Google on Bakoon's AMP-11R, AMP-12R, AMP-21R and Enleum's AMP-23R. Be forewarned. Should you peruse all logged reviews, you'll be busy for hours. I kid you not. But then you'll also know that no matter who listened then wrote about it, their response was invariably whoa. Once that table is properly set, we have the pertinent perspective on the AMP-54R. It means to go full-bore flagship. If this were a PC, it'd be called alienware. It's a high-end amp with true variable current gain so not a classic integrated with resistive volume control behind or in front of a fixed-gain circuit. It has multiple inputs and option cards for MC phono and LAN/coax/Toslink digital. In today's kilowatt class D scene, the power rating seems ho-hum. This Enleum mandates a different—dare one say more informed?—mentality. Again you be the judge on what your actual not imaginary power needs are. Having judged the lot but still being here, I can safely assume that we just cleared the two most obvious hurdles? Good, now we may proceed and jump into this pond's deep end: the sound. Splash? Or the perplexed silence of one hand clapping?

First we pummel perplexity on how to work this deck without visible switches, controls or typical display. Like the 20 stubby capacitors face down, so do the input and ± volume switches behind the lower right edge. Deciphering the LED-driven display is no more difficult. With 1-9 on the right—two lit adjacent bars indicate the between value—and 10-50 on the left, the AMP-54R can show 50 different SPL levels. Depending on eyesight, viewing this from afar is obviously far more vague than a classic numerical readout of appropriate size, even a big rotary with lit marker. Likewise the four light bars in the middle where certain combinations show one of seven inputs. It's how Soo In's Zen minimalism punishes us. Women can relate. They suffer for beauty all the time, be it in pointy high heels or starving themselves to fit an undersized dress. Making practical concessions for an ultra-sleek look is the third hurdle the would-be buyer of the AMP-54R must clear. Let's assume they're all masters of the pole vault. Now we're ready to turn on, tune in and drop the lot. Uff.

For mind over matter—understanding a circuit before we listen—this is the firm's 4th-gen version of a proprietary dual-mono current-mode discrete op amp. Its switched resistor matrix at the output sets gain whilst 32-bit software constantly monitors and auto-adapts the power transistor class AB bias for optimal performance without warm-up. This JET3 Bias goes beyond the AMP-23R's JET2 version. An ensconced low-rider power toroid doubles as mono footer to maintain Soo In's ideal of the skinny amp which seemingly defies gravity to float. No visible fasteners is another mandate of his so Enleum's best avoids them like the plague. The overall effect is back at alienware: a mini flying saucer from a more advanced race which crash-landed in California's Area 54. To skip from boring tech talk to ear talk in the seat, let's consider the rest classified information. We don't have the need to know more. We're focused on the central crux: given the AMP-23R's endless victory laps through our press, can the AMP-54R really scale up output power times four without booking any sacrifices in trade? In many an amplifier catalogue after all, the simpler circuits of fewer output devices so lower power sound better. With an AMP-23R in my possession, answering that will be this review's focus. To be fair to the AMP-54R, I needed speakers known to prefer more power and damping than the AMP-23R manages whilst easily going loud enough. I had just such a load: Qualio's IQ. That I usually run off Kinki Studio's 250-watt 2.5MHz direct-coupled class AB monos. The small Enleum has no SPL issue on them so on that score wouldn't play disenfranchised 2nd fiddle to bigger brother.