Hardware Reviews

Holoaudio Cyan 2 DAC proves that less is more

Holoaudio Cyan 2 DAC review https://the-ear.net

Holoaudio Cyan 2 digital to analogue converter

When Holoaudio’s European distributor, Magna Hifi, asked me to review Cyan 2, my excitement over being one of the first to hear Jeff Zhu’s redesigned, entry-level R2R digital-to-analogue converter was dampened a little by the realisation that this rather than the May DAC would be the next Holoaudio product gracing my listening room. The hulking two-box, top-of-the-line May DAC first appeared on my radar after Jason Kennedy reviewed the Spring 3 in 2021 and had been locked in my crosshairs since Zhu’s flagship headphone amplifier/preamp, Bliss, earned a place in my reference system almost a year ago. Once I’d spent a few days getting to know May’s newest sibling, however, I was reminded that you don’t always need to scale the mountain to experience a beautiful vista.

Cyan 2’s instantly identifiable black and copper anodised casework exudes the tank-like build quality and flawless finish of its pricier siblings but has a more desktop-friendly footprint of 30 by 20cm (12” x 8”). Holoaudio must be applauded for inspiring pride of ownership across its entire product line, this isn’t always at the forefront of manufacturers’ minds when they design for the most competitive end of the market but it is an excellent way to stand out in a crowded sector and encourage customer loyalty. Selling to customers through its two main distributors, Magna HiFi in Europe and Kitsune HiFi in the US, is certainly an advantage here. There are still, of course, limits on how generous manufacturers can be before profitability and product hierarchy is undermined and I suspect this at least partly influenced Holo’s decision to sacrifice not only the OLED display in favour of individual LEDs to indicate source input and sampling rate but also the option to internally oversample incoming data streams.

Holoaudio Cyan 2 DAC review https://the-ear.net

Diverging from both its predecessor and bigger brothers, Cyan 2 is now purely a non-oversampling or NOS DAC. Jeff Zhu favours the NOS approach to D/A conversion as he believes that incomplete information is less objectionable to our ears and brain than inaccurate information, the latter being the unavoidable ringing that occurs in the time domain in the quest for perfect frequency response reconstruction. The option of an onboard headphone output has also been dropped and input switching is now automated, a potential inconvenience for those with multiple sources as it may necessitate powering down or unplugging the ones you don’t want prioritised. The simplicity and uniformity of the LED indicators is very pleasing on the eye but it is a challenge to read the print beside the illuminated input and sampling rate from a distance. The LEDs are, however, laid out in a manner that’s easy to memorise. Cyan 2 retains its fully-balanced architecture and plentiful in- and outputs, so whether you have sources that connect by AES, coax, I2S, Toslink or USB, and preamps that connect by single-ended RCA or balanced XLR, all bases are covered.

Trimming non-essential features has allowed Zhu to focus on Cyan’s core function as a NOS DAC and Holo’s most affordable offering has been given a generous lift towards Spring 3 and May by increasing the maximum input sampling rates from 384kHz PCM and DSD512 to a cutting-edge 1,536kHz PCM and DSD1024. No commercially-available recordings have been made at PCM rates anywhere close to 1,536kHz and, although growing, the number of performances captured at DSD1024 is still minuscule. The main appeal of a DAC that accepts such high input sampling rates is the opportunity to externally oversample the data using more complex filters than those programmed into off-the-shelf oversampling chips to achieve superior performance.

Holoaudio Cyan 2 DAC review https://the-ear.net

A 16+16 R2R network handles PCM content while a separate, pared down 8+8 vector step resistor network takes care of DSD, ensuring both are converted to analogue signals from their native formats without remodulation. Other improvements include a galvanically-isolated USB input that uses proprietary firmware to achieve up to four times better performance on latency, transmission and eye pattern metrics, and a refined ‘de-glitch’ process that can apparently perform full-amplitude de-glitching without raising the noise floor.

Cyan 2’s impressive distortion and dynamic range specs shouldn’t come as a surprise given that Spring 3 and May are the two best-measuring R2R DACs on the market, showing once again that well-designed discrete topologies can hold their own against state-of-the-art integrated circuits in measurement wars.

Sound quality

Articulating Cyan 2’s sonics isn’t as straightforward as describing the character of a traditional NOS DAC that only accepts 44.1kHz and 48kHz sampling rates or an oversampling DAC that multiplies all incoming samples internally to a fixed PCM or DSD rate. The presentation you get from the Holo very much depends on the sampling rate of the music that’s piped in. There is, however, a natural ease, delicacy and refinement that pervades with all source material and provides a refreshingly different perspective from the unapologetic, hard-hitting Schiit Yggdrasil OG that’s been my reference D/A converter for several years.

Holoaudio Cyan 2 DAC review https://the-ear.net

Timbre and intimacy are prioritised when Cyan decodes the ones and zeros in CD rips streamed over USB from a Mac Mini in bit-perfect (NOS) mode. Instrument tones and textures are reproduced with an analogue warmth that’s all-to-often absent in oversampling converters. The gentle, textbook NOS roll-off in the high frequencies has a calming effect that focuses more of your attention on the message and emotion the artist is conveying and less on the recording’s production values, forming a closer connection between performer and listener. Bonnie Raitt is in the room with you as she lays bare her heart in I Can’t Make You Love Me, the pain in her voice mirrored so sensitively by Bruce Hornsby’s emotive piano accompaniment. This track tugs at the heartstrings no matter what converter is in my system but Cyan’s purer, more direct NOS delivery ensures it’s a tear-jerker.

When the Holo receives standard-res (44.1kHz) PCM that’s been externally oversampled to 32FS (1,411kHz), the presentational qualities approach those of authentic hi-res recordings to the extent that the differences between the two are much narrower than you’d expect. I first experienced this phenomenon when I reviewed Chord’s M-Scaler in 2019, a device that oversamples to 16FS (705.6kHz) using a proprietary 1-million tap reconstruction filter. Reproducing the highest frequencies without attenuation, Cyan’s soundstage grows both wider and deeper, and instruments are more clearly defined and positioned in three-dimensional space. The synth strings that are responsible for the lush and expansive soundscape in Duran Duran’s Ordinary World become even more sonorous, and it’s easier to discriminate the subtle vibratos of the individual notes that form the transcending chords that Nick Rhodes plays on his keyboard.

Holoaudio Cyan 2 DAC review https://the-ear.net

Steve Lukather’s melodic guitar solos in Toto’s underrated homage to the Beatles classic, While My Guitar Gently Weeps, are sadly a casualty of the ‘loudness wars’ and the track becomes more and more of a compressed wall of sound, both dynamically and spatially, as it builds to its climax. Upsampling this 44.1kHz recording to DSD instead of PCM allows Cyan to aerate to even greater effect what is a very congested mix by expanding the spaces between the densely-layered instrumentation, increasing the size of the stage, and revealing dynamic light and shade even in the loudest and busiest passages. The additional space that DSD manages to breathe into recordings isn’t without its compromises. World Party’s Is It Like Today is already sublimely organic and open-sounding and its conversion to DSD upsets the perfectly-judged balance of drive and flow the track has when enjoyed through the Cyan 2 in its native PCM form. Timing suffers as a result, the band’s performance becomes too laid-back, almost nonchalant, and the perceived lack of energy and conviction dissuades my feet from tapping.

I enjoyed being able to control the way the ones and zeros were reconstructed to suit my music, system and tastes. Most of my listening for this review was undertaken with headphones through Holoaudio’s Bliss and, while there were exceptions, I preferred no oversampling with ruthlessly revealing open-back headphones that have a natural ability to render large soundstages such as Audio-Technica’s ATH-ADX5000 and Sennheiser’s HD800S, and oversampling with more forgiving and intimate designs like Sennheiser’s HD600 and its variants. Sticking with Audirvana’s default SoX settings I’m sure I explored only a fraction of this DAC’s potential with external oversampling, but I was impressed by what I heard. The perceived improvements became more obvious as the multiplier increased so, if you do intend to oversample, I suggest picking the highest even-order multiplier your source is comfortable processing. While my ancient 2012 quad-core i7 Mac Mini executed Audirvana’s oversampling to Cyan’s maximum 32FS PCM rate without breaking a sweat, remodulating to DSD proved far more CPU-intensive and – after hearing only a subtle difference between DSD256 and DSD512 – I settled on the former to give the Mac’s processor an easier time.

Holoaudio Cyan 2 DAC review https://the-ear.net


The effortlessly smooth yet resolving presentation from Holoaudio’s most affordable resistor ladder DAC proves you don’t have to spend a king’s ransom to get a quality NOS implementation. Cyan 2 not only appeals to the purist who prefers listening to music without a digital reconstruction filter, but also the tech-driven tweaker who’s ready to jump off the upgrade wagon with a well-engineered, PCM- and DSD-native converter that can exploit the latest and greatest advances in external oversampling and remain current into the future. It’s this versatility and the sound quality it produces that makes the Cyan 2 a bargain.


Type: Non oversampling R2R ladder DAC
Distortion THD+N: PCM – 0.0005% @1K(-106dB); DSD – 0.0002% @1K(-114dB)
Signal to noise: PCM 127dB, DSD 115dB
Digital Inputs: USB, coax RCA & BNC, optical Toslink, AES, I2S on HDMI
Wireless inputs: none
Analogue outputs: single ended RCA, balanced XLR
Supported sample rates: PCM 44.1kHz – 1.536MHz, DSD 64 – 1024
Output Voltage: PCM 5V RMS XLR, 2.5V RMS RCA; DSD 2.5V RMS XLR, 1.25V RMS RCA
DAC: R2R ladder
Dimensions HxWxD: 48 x 300 x 200mm
Weight: 3.5kg
Warranty: 3 years

Price when tested:
€1.389 inc. VAT
€1.148 exc. VAT (customers outside the EU will pay the export price without VAT but will have to pay VAT and import duty on arrival.)
Manufacturer Details:



digital to analogue converter


Richard Barclay

Distributor Details:

Magna HiFi
T +31 (0)6 23 45 44 37

Notify of
Inline Feedbacks
View all comments