Review: Enleum AMP

Read just about any review of the Enleum AMP-23R and you’ll find likes and loves. This review will not stray from this well worn path of praise, so reader's who just want to know whether or not I like the AMP-23R, you can stop reading right here. I do.

The input stage of the AMP-23R employs a pair of the company's Ensense modules, one for each channel, which use "all discrete transistors with zero negative feedback and features an ultra-fast and ultra wide frequency response."

From Enleum:

"Gain Phase" is the name for our mechanical knob/display design as the shape of the dots resembles the moon phase. Circuit-wise, the difference is that the common method is to put a volume control in front of the input stage, but our circuit (or we call it "Ensence" for our input stage module) preserves the input signal and attenuates only after the input stage and is lossless. Because this doesn't alter the incoming signals from the very beginning, it allows uniform performance at all volume levels and is one of the reasons why our amplifiers excel at low volumes.

The AMP-23R's Class A/B output stage uses a pair MOSFETs from Exicon for each channel, whose bias is constantly monitored, controlled, and kept at optimum operating parameters by Enleum's JET 2 Bias circuit "resulting in more precise control…" and lower THD according to the company. Output power is rated at 25 Watts per channel into 8 Ohms (45W into 4).

I will note that adjusting the volume comes with a corresponding mechanical switching sound, not that uncommon, but it also generates a low level pop through the attached speakers or headphones, which is thankfully not at all common. This pop, which I could not hear when music was playing, is the result of DC-offset and Enleum has addressed concerns about possible damage resulting from it in an Instagram post:

Recently, we’ve become aware that there are some discussions about our amplifiers possibly damaging headphones or speakers due to DC output voltage. This has been already studied by us for many years as it is unique to our circuit design. We’ve been developing and producing our amplifiers over the decades, and we have experienced zero issues of damaging any other device. Unless the amplifier is faulty or malfunctions in some way, it is completely safe…

It's also worth noting that Korea's Enleum is the new brand name, as of 2021, of Bakoon International, a company founded in 2009. Soo In Chae is the man behind both companies and their products, and the AMP-23R is a direct descendant of earlier Bakoon amps, most directly the Bakoon AMP-13R. So this is a time-tested design.

The AMP-23R's insides are rather spartan with a very clean layout (my OCD is in love). This has led some people to question the Enleum's value, which reminds me of the silliness surrounding the original 47 Labs Model 4706 GainCard amp, which offered an even simpler circuit. A word of advice for people who enjoy using parts cost to gauge the value of hifi gear—imagine you have a job and you ask your boss for a raise who replies, "It costs you next to nothing to be here so why are we paying you anything above your bus fare?" Go ahead and argue that your time, experience, and expertise has value and before you know it you’ve started reasoning out why it's silly to use parts cost to gauge the value of hifi gear.

The front panel has but a single flush mounted power button that also acts as input selector. The headphone amp is tied into the same amp that's used to feed the speaker outputs which are automatically muted when using your ‘phones as the Gain control auto turns to its lowest level. My somatosensory system loved using that wheel to control volume as it fed back nothing but resistive pleasure while the little circular cutouts adjacent to the wheel turn partially then fully white, one at a time, as you adjust output level offering visual stimulus akin to 21 mini moon phases.

The included remote is a thing of equal beauty, tactilely, functionally, and visually.

Enleum has labelled the inputs "Voltage" 1 and 2 and those "Enlink" BNC connectors are for attaching future Enleum source devices (like a DAC) while an IEC inlet completes this picture.

One of the things I love about the Enleum AMP-23R is the way it looks coupled with the way it feels. Beautifully crafted and proportioned, the AMP-23R's height to width ratio is skewed higher than most, lending it an air of elevated elegance. The "Base Isolation Technology," also called a footer, is the result of a collaboration between Enleum and TAKT, a Korean company "specializing in anti-vibration technology for audio." Three thin circular silicon pads are provided to place under the footers to keep the AMP-23R from skating around like a penguin on ice—the metal bottoms of those footers are very slippery so I used the pads for better stability.

I mainly paired the 25W AMP-23R with the Barn resident DeVore Fidelity O/96 speakers, Auralic ARIES G1.1 Streamer (review) and totaldac d1-unity (review) using cabling from AudioQuest including ThunderBird interconnects, Robin Hood Speaker Cables, Diamond AES/EBU cable, and Thunder High-Current AC power cables plugged into an AQ Niagara 3000 power conditioner. The Box Furniture "Fallen A" held all components stylishly (to my eyes).

It don't mean a thing if ain't got that tone. Harmonic rightness is something I feel, I imagine most people do, as much a something I hear and the AMP-23R gets tone and portrays music in full bloom, so that familiar sounding instruments simply sound, and feel, right. Complete. Opener "Nothing's Free" from Angel Olsen's recent 4-song EP Forever Means features, prominently, Dan Higgins on sax and Drew Erickson on organ that swirls and curls around Olsen's lovely voice feeling positively wet and whirly and roller rink-ie. There's also a sweetness to the Enleum's way with music, with sounds having an inner light, that inner glow that we’re used to hearing from tube-based amplification that I find inviting and engaging in the best possible way. I would attribute this aspect of the AMP-23R's performance to its design (I bet you were expecting something more specific, but that would just be me pretending to know things I can't really know).

Lucinda Chua's vocals on YIAN are all willowy and whispery, about as intimate as intimate gets and the AMP-23R gets intimacy about as deeply as I’ve heard. When Chua first enters opener "Golden", her presence in Barn was startling because she felt close enough to know what she ate for breakfast. Kissing close. This slow moving record is a deep dive for me, and I revel in its melancholy embrace and through the DeVore/Enleum pairing the experience was ocean deep, vast in expanse spatially and emotionally. The AMP-23R is also a champ at presenting a physically involving and structurally believable sound image/world. This system removed any perceived barrier to entry, leading me directly into the music unfettered.

Overmono's debut album Good Lies, released on XL Recordings earlier this month, bounces and booms with danceable delight. Fun, funky, and sexy, this is electronic music that moves from the dance floor into the listening room with ease, aided by a fascinating cast of guest characters including St. Panther, Smerz, and Tirzah. This record is also whistle clean, with each element occupying its own sonic space and the Enleum amp ate up every last morsel and laid it out in Barn like a three dimensional mosaic hanging in space. Every edge, every sudden stop and re-start, felt perfectly portrayed as if the AMP-23R is somehow ahead of the musical proceedings, playing back from limitless seamless memory. Or to put it another way, the AMP-23R sounds capable of outpacing even the most frenetically paced music.

A lot of words have been spent on the Enleum as headphone amp and it's safe to categorize the majority of those words as running from positive to very (very) positive. And as you probably know, I’m not a headphone listener but I made a brief exception here because I wanted to hear what all of the fuss is about (seeing as the AMP-23R's headphone amp and the speaker amp are one and the same, I kinda know what's coming).

Jump On It by Bill Orcutt

I recently picked up Bill Orcutt's "Left over tour merch copies" solo acoustic guitar LP Jump On It, so recently the record hasn't arrived but since this was a Bandcamp purchase, I downloaded the free 24/44.1 file moments after purchase.

From the liner notes by Tom Carter:

But what's maybe more surprising is that Jump On It, with its living-room aesthetics and big reverb, packs a disarming intimacy absent from the formal starkness of Orcutt's earlier acoustic outings.

Disarming intimacy also perfectly captures what I was trying to get at earlier in terms of the Enleum's impact on me and my senses. Using the Barn resident AudioQuest NightOwl headphones, Bill Orcutt and guitar sounded exquisitely live-like, as if he was playing in my presence with all of his acoustic guitar mastery in plain sight. But playing isn't the best word to describe Orcutt on guitar as its more like he twists, contorts, and wrings sounds from those six strings stretched over a hollowed wooden body as if he is trying to squeeze every last bit of possibility from it, leaving behind a spent shell after things go silent. These six string sounds rang out true, directly into my head, feeling as real as when I bang away on one of the Barn guitars. Completely captivating.

Oren Ambarchi, Johan Berthling, and Andreas Werliin got together (again) for Ghosted a deep gentle groove of a record released last year on Drag City. Ambarchi on guitar although you’d never know it, Berthling on double bass, and Werliin on drums make music that crosses genres with ease—part jazz, world, experimental folk—all meant to ride that groove deeper and deeper still. The AMP-23R also loved this music, grabbing onto every subtle shade of color the trio coax from their respective instruments, and they are all master painters, with live-like dynamics and a sound image that defies its origin in reproduction. Shit sounds real, which translates into pure music connection no questions asked.

I could go on, and on, about some of the other music I sent through the Enleum amp but I’d just be repeating myself, minus the album-specific stuff. I also ran through a bunch of my favorite test tracks, which cover a very broad spectrum of genres and sounds and never once was the spell broken, not once was my one-on-one meditation with music disturbed. I also liked living with the Enleum amp, its modest size, superb build quality, and satisfying industrial design made its few minor quirks fade into irrelevance.

Some things just sing from the very first time you hear them. The Enleum AMP-23R proved to be one such piece of hifi kit, sending beautifully crafted and lovingly resolved music into the Barn from track 1, feeling as good as a cool Spring breeze scented with wildflower perfume gently turning our sheer bedroom curtains into dancing ghosts.

Spending time with the Enleum AMP-23R proved to be all enjoyment all the time as it presented all of the music I sent its way with disarming intimacy and beauty. The only negative that bubbled to the surface as the review period was coming to an end was a wish for even more time with the AMP-23R to explore the endless stream of wonder that music has to offer.

Enleum AMP-23R Reference Compact Amplifier Price: $6250Company Website: Enleum

Specifications

Maximum Power: 25 watts (8 Ω, 1 kHz) | 45 watts (4 Ω, 1 kHz) | 4 watts (60 Ω, 1 kHz)Gain: 22.5 dB max (Speaker, Headphone High) | 7 dB max (Headphone Low)Gain Control: MPU Controlled Stepped AttenuatorFrequency Response: 10 Hz ~ 100 kHzInput Impedance: 10 kΩ (Voltage) | 10 Ω (ENLINK)Input: 2 Voltage (RCA) | 1 ENLINK (BNC)Output: 5 Way Speaker Binding Post | 1/4″ Headphone OutUser Interface: One Button & Gain Phase Control | Remote ControllerPower Consumption: 30 watts (Idle) | 100 watts (Max)Dimensions: 230 mm (W) x 230 mm (D) x 55 mm or 82.5 mm incl. Isolation (H)Weight: 4.0 kg (net) | 4.5 kg (shipping)