November 2019

Manley Labs Absolute Headphone Amplifier / Preamplifier
Rare Form: Manley creates a Masterpiece that looks and sounds like nothing else!
Review By Dave Hanson

  I had the pleasure of meeting Manley Labs VP of Engineering and Design, Zia Faruqi, in the CanJam exhibit at Rocky Mountain Audio Fest 2018. While I was more than familiar with the Manley name, this was the first time I had seen them in the personal audio section of the show, so naturally I was quite curious about their debuting flagship headphone amplifier, the Manley Labs Absolute Headphone Amplifier ($4500). Zia was very generous with his time, and walked me through the devastating and inspiring story behind the amplifier's creation. Just a few years earlier, Zia's wife lost her life to cancer. Lost and looking for something, anything to bring back his sense of purpose, he reached out to his long-time friend, EveAnna Manley, who took him in and helped him get back on his feet when all was lost. Zia would find purpose and inspiration again with the seed of an idea – a headphone amplifier with a strikingly original and elegant design, which would eventually become the Absolute.

Zia and EveAnna collaborated to bring the Absolute to life, pairing Manley's innovative approach to amplification with Zia's first-class design skill. The result is an amplifier that looks and feels like no other. While many other amplifiers tend to look like boxy DIY projects or science experiments, the Absolute is elegant and curvaceous. Where others are strictly utilitarian, Absolute is refined and purposeful. To say it is an achievement in design would be an understatement of criminal proportions.

Manley Labs' Absolute is long and thin, with the top designed to double as a rack to hang your headphones. Each side has an elegant cutaway, allowing the amplifier to be easily moved while it is still warm. It's punctuated with a wood grain on the top and sides, and a semi-transparent molded black plastic top that allows you to see some of the circuitry inside. The cleverly-crafted transformer sits in the rear of the amplifier, climbing vertically behind the slope of the top plate.

Features Galore
Every bit as clever as the design is, the circuitry and feature set inside are even more crafty. The Absolute allows the listener an unbelievable amount of versatility to tune the sound to their liking. A button on the front allows the ability to toggle between tube operating modes, switching from push-pull to single-ended on demand. There is a short delay of about three or four seconds and then the amp swaps operating modes. Hearing the difference was quite fascinating. I found the push-pull mode was a bit cleaner, but in many cases I preferred the additional grit and emotional gravitas of single-ended operation.

Another very cool option is the negative feedback dial. Turning the dial counter-clockwise added more negative feedback to the signal, lowering distortion at the cost of a small amount of volume, which I learned to easily dial back in simultaneously on the volume potentiometer. Turning the knob to the right removed negative feedback, increasing the Absolute's very pleasurable harmonic distortion. This was a very nice effect for adding a bit of sweetness into the vocals or instrumentation. Most of the time I found myself with the dial positioned at about two o'clock – with just a little bit of negative feedback in the mix, maybe about 33%, or so. But the options don't end there.

The Manley Labs Absolute also features a mute button, mono mode, dials for balance and EQ, plus a selectable impedance switch to match with your headphones. I found the EQ in particular to be phenomenal. First, I should mention, it is fully bypass-able with the push of a button for the purists out there. But once the EQ was engaged, the bass and treble boosts were very well implemented. Dialing to 12 noon would offer a neutral presentation and you could adjust up or down from there. Testing with electronic music, turning up the bass left me with a big stupid grin on my face. The curves never left the music feeling woolly or zingy.

Furthermore, the Absolute can also serve as an outstanding stereo preamplifier. Wiring it into my two-channel system, I noticed an immediate improvement in bass impact and rumble, along with more holographic imaging. The EQ worked equally well here, and I actually picked out a couple of details I hadn't noticed before on both ends of the frequency spectrum!

Another nice feature that goes with the preamplifier function is the volume pot, which is a encoder wheel driving a precision relay attenuator system that has a string of lights running left to right across the front to indicate the volume. Each evenly-spaced volume step comes with a satisfactory click, and there's no hassle moving between large and small volume gradations. The Absolute also includes a radio frequency remote, that is robust to say the least. In a pinch, one could probably use it as a weapon. It should be noted, the remote only controls volume, none of the other features.

The back of the amplifier features two RCA inputs and three outputs – preamp RCAs, a 6.35mm headphone output, and a balanced XLR output. Design-wise, this was the only area where I really had any criticism. Plugging your headphone into the back of the amplifier can leave you a little short on cable at times, which can be a little bit of a pain, depending on the placement of the amplifier. I also felt selecting the inputs and outputs could be a little bit of a pain, just trying to see that the proper lights are engaged. Certainly, a very minor complaint, but there were a couple times where I wasn't getting sound, only to realize I was looking at the indicator light from the wrong angle.

One Good Watt Is All You Need
Much like the design of the Absolute, the sound is exceptionally refined. The Absolute offers about 1W of power, but it's, as they say, "One good watt." I didn't have much trouble driving anything with it. It played well with the power-hungry Abyss, 300 Ohm headphones from Sennheiser and ZMF, and exceptionally well with the HiFiMAN HE1000se. Bass has exceptional body and extension, and was able to take the HE1000se down to the very lowest notes with presence and body you rarely hear. If I had to describe it in one word, it would be BALLS. If I have three words, BIG BRASS BALLS. There is just a level of power and grunt down low that you don't always get with other amps, and you definitely don't expect it, looking at the elegant and somewhat diminutive Absolute. But don't let the looks fool you, this puppy has power down low for days. As a headphone amplifier and a preamp it over-delivered.

Midrange is glorious and tubey, without ever feeling bloated. The choice of features will dictate your experience here. Do you want it clean, punchy and by the book? Switch to push-pull and dial in some negative feedback. Do you want it sweet and emotionally engaging? Switch to single-ended and turn down the negative feedback to bring in more tubey harmonics. The Absolute gives you a ton of versatility, especially when it comes to the way you hear the midrange. I mostly found myself preferring the latter presentation, with a more "wet" sound. The tube distortion here is absolutely top notch and very emotionally involving, so I say dial it in!

Treble is very transparent, airy and grain-free. Testing with the HiFiMAN HE1000se, the Manley frequently helped the headphone "disappear" off my head, putting me into the room with the performers. Roll-off and grain of any kind can easily distract from this transparency effect, but the Manley is able to pull it off with the greatest of ease.

Sounds emanate from thin air at very precise latitudinal and longitudinal distances around you, forming a very believable three-dimensional stage. The pure open air created by the excellent treble and nicely black background makes the imaging seem all that much more pinpoint, particularly when paired with a headphone like the Sennheiser HD800 or HiFiMAN HE1000se. Imaging was also very spot on during two-channel testing, where I noticed a sizeable bump in depth specificity and holography. Details spring to the surface easily, but not in a way that distracts from the rest of the music. Testing several sources, I was able to reliably hear the differences between my Hugo 2, Pro-Ject Carbon and the LampizatOr Amber 3. The Manley was able to easily decipher the nuances in timbre, resolution depth, punch, staging, ambient micro-detail and deep inner detail. As a piece of reference gear, that is what you would hope for.

Final Verdict
It's rare that you come across something that is so totally different. I've brought the Absolute to a couple of headphone meets, and the reaction is always, "Whoa! What's this?" People are always impressed with the sheer quantity of options, and it is fun to see their faces light up when they hear the difference of switching from single ended to push-pull or turning the negative feedback knob. It's pretty hard to fault the Manley Absolute on any front. It's a beautiful design, flush with fun options that make it an absolute joy to play with, and it sounds absolutely fantastic to boot! Furthermore, it excels as both a headphone amplifier and a stereo preamp, which makes the high price tag ($4500) a bit more palatable. In both cases, it was highly transparent, holographic, very punchy and well extended on both ends of the frequency range.

Perhaps the only thing more compelling than the sound and design is the incredible and inspiring story behind the amplifier itself. It is one of tragedy and triumph, and a valuable reminder that no matter how awful life gets, there will be another chapter. Sometimes it just takes a good friend to help bring out our best again.

Equipment Used During Review
Sennheiser HD800
Abyss AB-1266
ZMF Verite Closed
ZMF Verite
ZMF Aeolus
Hifiman HE1000se
Hifiman HE500
Campfire Andromeda
Stax L300 Limited
ELAC Uni-Fi UB5
Wells Audio Milo
KGSSHV Carbon 
Glenn OTL Tube Amplifier
MonoPrice Monolith Liquid Platinum
Bellari VP-130
Virtue Audiophile 2
Chord Hugo 2
LampizatOr Amber 3
Pro-Ject Carbon
DanaCable Lazuli Headphone Cables
DanaCable TruStream USB
Wireworld Starlight 7 USB
DanaCable Onyx Interconnects
Wireworld Electra 7
Pandora AC-9 SE
Pandora AC-14 SE
DanaCable PowerForce
Pandora Vulcan
Schiit Wyrd
Uptone USB Regen
PS Audio Duet
Audirvana
Tidal HiFi

Specifications
Type: Vacuum tube stereo preamplifier and headphone amplifier
Amplifier Topology: Switchable Single-Ended or Push-Pull
Vacuum Tubes: Two 12AX7 (ECC83) and four 6AQ5A (EL90)
Inputs: Two unbalanced RCA 
Outputs: Stereo pair RCA, one 6.35mm, and one 4-pin XLR
Maximum Input Level: 7.7 VAC RMS (+20 dBu)
Volume Control: Precision Stepped Relay Attenuator 0.5dB per step, -63dB total attenuation 
Output Impedance: Switchable: Low 12 to 50 Ohm, Mid 50 to 200 Ohm, High 200-600 Ohms
Maximum Output Power = 1W into 12 Ohms BW 22Hz to 22kHz
Variable Feedback Control (FB): MIN 0dB, MAX 10dB
Signal to Noise Ratio: 83dB (1kHz sine wave, 100mW output, BW 22Hz to 22kHz)
Frequency Response, Push-Pull: Flat 10Hz to 20kHz (-1dB @ 40 kHz)
Frequency Response, Single-Ended: 20Hz to 20kHz (-0.5dB @ 10Hz, -1dB @ 50 kHz)
Distortion, Push-Pull: 0.16% THD+N (BW 20Hz to 22kHz)
Distortion, Single-Ended: 1.0% THD+N (BW 20Hz to 22kHz)
Unit Dimensions: 11.5" x 5.5" x 8.2" (LxWxH) 
Unit Weight: 12 lbs.
Power consumption STANDBY mode = 0.5W, Max Power = 80W
Price: $4499

Company Information
Manley Labs
13880 Magnolia Ave 
Chino, CA 91710

Voice: (909) 627-4256
E-mail: sales@manleylabs.com 
Web: www.Manley.com