Rarely does anything from the other side of the audio fence generate much interest among audiophiles and music lovers in the high-end audio industry, but Abendrot STUTE True Audio Master Clock Generator and HENGST True D/A Converter for STUTE are a different breed of cutting-edge digital products, with the undisputed submarine-like depth experience from pro audio.

So when Ryuji Seto of Abendrot asked me about the possibility of testing STUTE and HENGST, I had no qualms about listening to and exploring this state-of-the-art digital combo. And as you can read on, I was more than thrilled with what these unique creations from The Land Of The Rising sun have to offer.


Abendrot was founded by a dedicated team of prominent master clock engineers and digital audio designers in the UK and Japan, to provide the very best in digital sound reproduction. Developed through the master engineering of experts with over 30 years of experience and an abundance of passion in the design of various circuits, Time aligned, the Abendrot products are correlating with an inspiring hundred-year milestone in audio history that especially in past decades almost exceeds the limits of what was previously seen as not possible.

Abendrot crafts their product with fanatical dedication. Every Abendrot product is individually and meticulously crafted by hand. The level of attention and precision of these top-tier fine boutique manufacture products was inspired by the complexity and painstaking forming of the ancient Japanese samurai swords. These iconic objects of desire are still comprised with a mysterious aura that transcends the usual limits of manufacturing as they are elevated to the level of individual art.


In the era of organic analog sound, the time when music was most loved, there was no digital noise and loss of information due to clocks, synchronization, etc. With STUTE, Abendrot had envisioned and presented the first solution to the theorem and also a criterion, to begin with. Abendrot's master clock technology is the result of the dedication and passion of high-end master clock engineers and analog/digital audio professionals.

As a start, the Abendrot Everest 701 - True Audio Master Clock was born from the dream of taking HD audio to the next level. 

The original challenge was the quest to find and experience the very same fascination that can be derived feel from old records, but in the present ear and with the digital medium. 

Before finalizing and put it into existence their master clock, the Abendrot team never experienced digitally produced sound with such transience and depth. This gave them a green light to research the subject matter even further and create something of meaningful difference. 

Following the idea that digital audio reproduction is possible without any loss of information, the Abendrot team couldn't help but feel the possibilities of the coming era of music production and reproduction. 

With these assets and attributes, Abendrot envisioned the new reality where artists, producers, engineers, and anyone who is seriously inclined with the highest quality of music production and reproduction would share similar affection. 

With all that in mind, the real question emerged. Why use and implement inferior master clocks that inevitably cause information loss? 

Consequently, Abendrot started to manufacture master clock signals that are perfectly matched to digital audio systems, making it the be-all and end-all of digital audio recording, the ultimate reality. 

There's no doubt how we're witnessing the new dawn of high-definition, state-of-the-art digital audio, and Abendrot has conceptualized their products from the ground up to operate with the same organic quality as what analog stands for. 


STUTE, an Abendrot debut product, is a rubidium master clock designed specifically for apex digital audio systems. Using Abendrot's exclusive technology, STUTE produces the coveted 10MHz signal that is ideal for digital audio. Some of the world's most renowned and passionate master clock engineers focused on the nearly impossible task of reproducing a near-perfect time axis - a key factor in creating the ultimate digital playback experience now known as STUTE. 

Abendrot firmly believes that STUTE is a monumental product that may finally be able to realize the ultimate ideal for digital audio: To surpass the qualities of analog playback. This ultimate master clock produces the most precise and sophisticated clock signal the industry has ever experienced, with near-perfect digital-to-analog conversion. 

From the ground up, the Abendrot STUTE, when paired with HENGST, was envisioned as the ultimate audio combination to take the listener to an unimagined frontier far beyond the capabilities of existing analog and digital sound reproduction methods, bringing those blissful moments from a concert hall to the walls of the private listening room.


HENGST DAC is the result of over three years of intensive development with the sole aim of reproducing the purest possible audio sound. Using Abendrot's new Transfuse Clocking technology, HENGST is optimally designed to preserve the quality of audio conversion achieved by STUTE's near-perfect 10MHz signal. 

By completely separating the digital audio and clock signals sent from the AES /EBU and S/PDIF inputs, HENGST realizes the conversion of pure digital audio to analog audio. The articulate and strikingly expressive characteristics of HENGST guarantee that original emotions will be intensified at every moment that the audio drama takes place, from the fraction of silence before the sound pours into the air, to the moment when the rich and dynamic sound disappears again into complete silence, greatly enhancing sensations. 

Abendrot firmly believes that HENGST embodies something timeless and extraordinary with its high-precision digital audio technology.

As you can read throughout the review, HENGST and STUTE are indeed opening a few of the new aural frontiers.


Here are some of the typical audio connection examples of STUTE and HENGST. Abendrot Audio's top quality master clock signal can be sent to external devices with a 10MHz signal input.


Folk Singer is still one of my favorite acoustic blues records. You should get your money's worth with this iconic Muddy Waters recording on a properly set up and balanced high-end audio system. 

There are so many tiny details hidden in this record and Waters's enormous presence was superbly captured and ghastly real. Not just in the digital domain, but with analog as well, even some top-tiers fail to replicate Waters' mojo. He's almost 6 feet tall, and when he "howls" the listener should have an immense collision of drama, energy, and thunder-like energy thumping the whole body. 

It's hard to pick a favorite track from the album, but "My Home Is In The Delta" has a special emotional impact that hits me every time.  When everything is set properly in the system, Waters should be presented in full size along with a majestic sonic expansion of space. 

Abendrot STUTE and HENGST not only mapped "My Home Is In The Delta" with pinpoint accuracy. The holographic representation of the recording venue was impressive, with sound escaping from the speakers and walls. 

Buddy Guy accompanying guitar playing was gentle as a hummingbird while in juxtaposition being accompanied by Waters whale-like enormous power. All this was set into effect without letting the music drift off.

But it's not only about Waters's vocal tumultuous roaring peak. At moments especially on "Long Distance Call" he almost, literarily tear-off the guitar wires creating the dynamic tension, that is not easily reproduced. This creates a particular phenomenon where note leading-edge speed and energy correlate in a distinct perplexity. I watched in awe and amazement how effortlessly this sonic collision was revived with STUTE and HENGST like it was the most ordinary affair. 

But  STUTE and HENGST excel in far more diverse realms.

The level of acoustic anchor points far exceeded what I somehow expected, and this allowed for a unique horizontal and vertical expansion as well as an unaltered tempi. 

This was easily deciphered with “Vivaldi's Song” from album Burchfield Nines by Michael Franks, expertly produced by Tommy Lipuma, and recorded and mixed by no other than legendary Al Schmitt.

Frank's soothing voice, his leitmotiv musical kaleidoscope were beyond entertaining with STUTE and HENGST. The ongoing, shifting tempo was effortless to follow, without the subtle timing drifts that are not absent even with some of the top-notch digital front-ends. 

For decades I've experienced Frank's songs as lingering deep and as the mixture sweep of Akira Kurosawa's Dreams and Paul Gauguin paintings, yet the Abendrot STUTE and HENGST combo has uncovered even further, newfound details and revealed further layers of "Vivaldi's Song". That alone is a remarkable discovery alone worthy of all the high praise. 

STUTE and HENGST zen-like tranquility, where nothing is out of balance or taken to extremes, was further revealed with Pat Metheny's "Same River" from his album From This Place.

The whole album is infused with a dramatic touch, complex soundscapes, and a highly magical narrative that is likely to touch the hearts of people not normally moved by Pat Metheny's compositions. 

Even in the absence of Lyle Mayes, the magic continues; a little different, but Metheny's majestic phrasing, technique, and lyricism is not only as good as before but evolves beautifully. 

Abendrot STUTE and HENGST have once again shown how their combined inner cores can communicate the music with a kind of koan quality. 

With STUTE and HENGST in action "Same River," multi-layered instruments and their tones felt like life-charged particles sweeping beautifully across the sonic canvas, once again unfolding a newfound sonic escapade. 

For me, there was never any question as to why Metheny chose Antonio Sanchez as his second heartbeat, and Abendrot STUTE and HENGST made me dive deeper into apprehending Sanchez's undisputed and unrivaled sense of rhythm and pace.

It's been a long time since I've practiced percussion, but I can still fully appreciate and remember how complex polyrhythms are. Especially when you get into syncopation. Some musicians explored beyond norms the microtonality in all its complexity. Micro-timing wise I've could similarly comprehend Sanchez's unprecedented micro-timing. 

Abendrot STUTE and HENGST have decoded one-of-the-kind lock and load with control up to the nines. This is, without a hint of a doubt, closely related to STUTE's extremely precise inner ticking.

Abendrot STUTE's and HENGST's ability to sustain the pastel-technicolor-like quality of timbre, tone, and color, unenhanced by the luminous spectacle of sound, where even the smallest shifts and progressions have their significance, has been continued from album to album, from track to track. 

No doubt about it, STUTE and HENGST were made by music lovers for music lovers, with a perfectly balanced, cutting-edge aural statement.


There is no question that timing is of paramount importance, especially in pro audio studios. Along with phase, these are the two attributes that any serious producer, mixmaster, or mastering engineer will readily agree with. Especially when it comes to the sonic pinnacle and when the audio setup, room allow for such designations. Of course, the ancillary equipment must follow suit for the overall experience to fully unfold. 

The Abendrot STUTE and HENGST combo offered a new, refreshing and sobering experience and acted as a clear reminder of how important the external master clock, of for the fact the internal clock of a DAC is when it comes to sound.

Properly addressed timing is reflected in the density of complex time minuscule entities and fractures consisting of quark-like micro-decays, delays, and anchor points that are constitutive of recreating the full sound spectrum and, more importantly, a believable illusion. Our auditory mechanism is highly sensitive to timing (and phase), and when properly addressed, we recognize this quality immediately and in all its prominence. 

And that is truly the case with STUTE and HENGST. If I had to sum up their strengths and reason for being, it would be credibility and believability. In the studio, there is nothing more important and outstanding than getting everything as close as possible to the essence of the original instruments and human voices. Even with electric guitars, synthesizers, and other non-acoustic instruments, the key is to nail the sound as it is. And this philosophy has undoubtedly been fully realized on STUTE and HENGST. 

Without objectively and convincingly shaping the golden triangle of timbre, tone, and color, there is no high-end designation or powerful sticker that is so often overused.  STUTE and HENGST pack both and goes even further.  

The remarkable combination of Abendrot STUTE and HENGST provides a clear, transparent window into the music, where there is no artificial glare or saturation. 

Think of it like the crystal clear mountain water that is not only diamond clear in form, but also offers an invigoration and purity of flavor that immediately enters the veins and creates a completely immersive, out-of-this-world sonic journey.

Similarly, Abendrot STUTE and HENGST effortlessly bypass the usual sensory guards and allow the music to unfold and decode it with the most essential core. 

Although I've been an analog lover and enthusiast for decades, I've been a strong advocate for the significant (r)evolution of digital audio in recent years. The most highly over-chewed clash of titans between analog and digital has finally found its equilibrium. But not exactly in the circumstance that the extreme defenders of both camps would like to see. On the opposite. The healthy coexistence of analog and digital, in which the digital has finally reached an impressive level of sonic panache, in which it no longer has to compete with what has always been seen as its mortal counterpart. It can finally exist for itself with its qualities. 

And Abendrot STUTE and HENGST are perfect representatives of this new breed of digital devices, coming along with a constitutional quality that lifts them far above and beyond mediocrity. 

Abendrot STUTE and HENGST have a beautiful, zen-like timeless aesthetic that makes it immediately apparent how these devices are special with their zen-like sculptural gold and silver premium-style aluminum cases. 

Abendrot STUTE and HENGST majestic appearance and sonic impact still last for days upon heading back to the Land Of the Rising Sun. 

There is something about the aesthetics and sonic aura of the STUTE and HENGST that reflects the true spirit of proud Japanese heritage. These digital gems are splendidly crafted with the greatest care taken on all front to preserve and reflect the music at it is.

Reviewing and discovering such gems is a real luxury of my job and not gaining this particular insight would cost me a precious experience and reference for my current and future evaluation endeavors. 

I am pleased to acknowledge the work of Ryuji Seto and Abendrot with Mono and Stereo Upper Echelon Product Award. 

Matej Isak 


  • STUTE 46,000.00 USD 
  • HENGST 39,000.00 USD 



Amplifier Output  

  • Output frequency : 10MHz sine wave
  • Output channel : 2 output (Stute) 
  • Output connector : BNC female
  • Amplitude : 1V RMS 50ohm

Rubidium Unit

Phase noise : 

  • less than 140dBc / Hz (100Hz)
  • less than 150dBc / Hz (10KHz representative value) 
  • Accuracy at shipment : ±5×10-11
  • Warm-up time : less than 10 minutes (time required to lock and gain practical accuracy)


  • Input Voltage : 115V / 230V , 50-60Hz
  • Wattage 30W(typical)


  • Operating temperature Range : 5℃~ 35℃
  • Relative humidity : 35~85%RH(non-condensing)


  • Size : 440 x 420 x 90mm (W x D x H), Weight : 11.5kg

※1. This product is manufactured on a per order basis.

※2. The design and specifications are subject to change without prior notice for product improvement. 


Digital Input

  • Input 1 AES/EBU XLR 110Ω x1
  • Input 2 SPDIF Coaxial RCA 75Ω x1
  • Sampling Rate 16-24bit 44.1kHz-192kHz

Analog Output

  • Converter Type : Complete Balanced Dual Mono Wide Dynamic Range Topology
  • Output : XLR Balanced L/R
  • Output Amplifier : High Voltage Buffered Wide Range DC Amp
  • Output Impedance : 100Ω (ATT 0dB)
  • Output Signal Level : 9VRMS Hi-Z weighted (ATT 0dB)/4.5VRMS Hi-Z weighted(ATT -6dB)
  • Output Attenuator : 0dB/-6dB Hi-Z wighted
  • SN Ratio : better than 115dB TYPE
  • THD+N : better than 0.002%

Clock Synchronized Circuit

  • Input : 10MHz 1V RMS 50Ω/5V P-P Hi-Z
  • BNC : x1 (Auto Synchronize Connection)


  • Input Voltage : 115V / 230V , 50-60Hz
  • Wattage 30W(typical)


  • Operating Temperature Range 5℃~ 35℃
  • Relative humidity : 35~85%RH(non-condensing)


  • Size : 440 x 420 x 90mm (W x D x H), Weight : 11.5kg

※1. This product is manufactured on a per order basis.

※2. The design and specifications are subject to change without prior notice for product improvement.

※3. The provision of a 10MHz signal from an external device is mandatory for the operation of this product. 


Abendrot International LLC

#202, 5-11-23 Minamiaoyama Minato-ku

Tokyo, 107-0062, Japan

Tel : +81-3-6312-8310

Fax : +81-3-6369-4230

Web: abendrot-audio.com

Email: link