In this review we look at the Topping Centaurus R2R DAC. It is a cooperation with HOLO Audio and the unit is selling for $999 USD at this moment. This is the first article of Rudolfs!

Disclaimer: Topping sent us the Centaurus FOC for this review in exchange for our honest opinion.

Intro

In this review, I’ll try to determine whether the new Centaurus R2R DAC is more Topping or HoloAudio. The unit costs $999 USD and can be bought from Shenzhen Audio, HiFiGo, and other retailers.

HoloAudio is the brainchild of the audio designer Jeff Zhou. The brand started gaining the attention of music lovers around 2016 with the introduction of Spring DAC. It’s an R2R-based design with a linear power supply and equally eye-catching exterior and interior. Since then HoloAudio has released audio electronics in most categories with the venerable Spring DAC on its third iteration.

Topping on the other hand has always been an engineer’s darling brand. With designs based purely on measurement excellence, the brand has garnered a lot of fans and caused some controversy among listeners about whether standard electronic signal measurements translate to listener preference. With the release of higher-end offerings Topping has been presented with a problem – why bother paying more if even the affordable products reach seemingly absolute transparency? We have reviewed many Topping units here on Headfonia, you can all those here.

Topping x Holo Centaurus

Enter the Centaurus

Like the recently reviewed D90 III Discrete, the Centaurus is Topping stepping into Terra Incognita. Before the company worked with well-known converter chips from the industry greats like ESS and Asahi-Kasei and now the Centaurus is their second discrete DAC. Unlike the D90 III Discrete which was a 1bit design, the Centaurus is based on a 24bit R2R ladder designed by HoloAudio. The rest of the circuit is all Topping.

Let’s first get the hottest issue out of the way – yes, the R2R DAC board is the same HoloAudio Cyan 2 uses. And no, there’s no way the Topping Centaurus is the same DAC only cheaper. True to its design philosophy the Cyan 2 uses a linear power supply, galvanic isolation for USB signal, and a different semi-discrete IV stage after the DAC board.

The Topping part of the Centaurus uses an SMPS which generates a working voltage which is then converted via switching converters to other voltages as needed. Generally, the trade-off here is that linear PSUs have mains and ripple noise to contend with while switchers can have ultrasonic noise both in the power rails and radiate it onto nearby components.

While the Centaurus doesn’t employ galvanic isolation, it does use Topping’s proprietary jitter suppression circuit to achieve very respectable numbers. On the other side of the DAC board, we have Topping’s newest IV stage circuit, which I first encountered in the D50 III. It will likely sound different from what Jeff Zhou has cooked up in the Cyan 2.

While already seen in the Cyan 2, the R2R board is worth discussing as well. Unlike most other resistor ladder DACs, it features a composite structure with 8 dedicated arrays. Four of the larger resistor banks handle a 24-bit PCM signal, while the other four are 6-bit arrays dedicated solely to DSD decoding. So, in a way, we get two DACs in one package.

The Cyan 2 was much lauded for its powerful digital front end with up to DSD1024 and PCM up to 32Bit 1536kHz data stream ceiling. The Centaurus can only do half that but it has one last trick up its sleeve that will certainly be more audible – 10 band parametric EQ! Dial it in correctly and it can rescue many headphones and speaker systems from unwanted coloration.

Features:

• Up to 32bit 768kHz PCM and DSD512 signal support
• Bluetooth 5.1 – LDAC/aptX-Adaptive/aptX/aptX HD/AAC/SBC
• Inputs – USB-B, RCA SPDIF, Toslink, AES/EUB, HDMI LVDS I2S and Bluetooth
• Outputs – RCA, XLR
• 3.5mm trigger input and output (12V)
• SNR and DNR – 130dB (well below audibility)
• THD+N – <0.0005% (well below audibility but lower than expected for Topping)
• 2/4Vrms and 2.5/5Vrms output voltage modes
• Output impedance – 50 Ohms (RCA), 100 Ohms (XLR)
• 10-band parametric EQ
• Digital volume control
• Defeatable oversampling
• Remote

Topping Tune PEQ

To configure the built-in DSP engine of the Topping Centaurus (and D50 III, D90 III Discrete) the Topping Tune desktop application has to be used. Currently, it’s available to download for Windows from the company website. After a short installation procedure, it opens up the configuration UI which should be familiar to anyone who’s worked with PEQ previously.

On offer are 10 PEQ bands which can use peaking, low, and high-self as well as low and high-pass functions. There’s also a pre-gain knob to lower the overall again depending on how much the overall PEQ peaks over 0dBFS to avoid clipping. An automatic anti-clip checkbox would have been handy so I don’t have to eyeball the exact amount to cut.

Currently, Topping Tune allows for importing and exporting the PEQ configs in text form. I would like that they’d add native support for Squig.link EQ files as that would make life easier for many EQ fiends who use that platform. The gain limits are +/-12dB which is more than fine for headphone and room tuning. More bands can be piled on top of each other to cut or boost beyond that.

I used to be an avid DSP zealot in the past but lately, I’ve mellowed out a bit. At the same time, I still think that a well-tuned EQ can be a game-changer for most systems out there. Having this functionality in a DAC is highly convenient as there’s no need to run extra software and non-computer-based audio systems can benefit as well. This feature currently is a great market differentiator for Topping over its peers.

Design, Build & Haptics

The Topping x Holo Centaurus comes in a medium-sized black cardboard box. I won’t say that the gnarled finish exactly exudes luxury but it’s better than plain cardboard. After sliding the lid off we see the DAC sitting snuggly in a foam cutout. In a neighboring cutout, we get a box with an AC power cable, a USB cable, and the remote.

In terms of design language, the Centaurus is an odd choice for Topping. It shares the basic cues of 70-series gear, yet the price point obviously signals a 90-series product. Dominating the center stage of the faceplate is a black tempered glass square which reveals a color LCD when the Centaurus is operational. I immediately saw the stand-by button and two directional buttons, however the three touch sensors right by the screen eluded me for the longest time.

Short-pressing the standby button switches between RCA, XLR, and all outputs for signal routing. Do note that the volume setting for each output isn’t remembered, so if your powered speakers take the signal from the RCA output and the XLR is used by a headphone amp, there’s a chance to accidentally feed a full amplitude signal to the speakers. Ask me how I know. The up/down buttons change the volume which is fine but I would have preferred an encoder knob for that.

On the back, we get the usual bevy of I/O. RCA and XLR for blasting out that sweet R2R analog signal and RCA, Toslink, USB-B, LVDS I2S, AES/EBU for their respective digital formats. And a nice small Bluetooth antenna for when your buddies are over. My only gripe is choosing RCA for SPDIF – most implementations can’t abide by the 75 Ohm wave impedance and will cause line reflections. More work for the Topping jitter suppressor.

In use the Centaurus is pretty innocuous – no relays to be heard and it doesn’t get hot. So not very audiophile in that sense! The screen is very nice to look at though. It’s the same that the D70 Pro Sabre uses and as far as DAC screens go, I like it very much. Switching on the UV meter visualization looks great but it obviously delivers only a fraction of the charm of a real dancing needle meter. The FFT spectrograph is way more useful but I wish the low-end bands would go below 50Hz.

Sound Signature & Technicalities

I have heard numerous Topping DACs and I’ll reveal right away that there is some family DNA in the Centaurus despite HoloAudio contributing. In short, the sound could be described as “Topping in love”. Yes, there’s the precision we’ve come to expect from the analyzer-first brand but this time there’s a lot more heart. It’s no wonder they’ve put the Centaurus under “Other” on their DAC product page because it really is markedly different.

Almost all of my listening was done via the USB input from my desktop PC. Other wired inputs yielded identical sound so I just stuck with USB which also allowed me to store PEQ configs effortlessly. I found Bluetooth fine for party mode but it doesn’t have lossless so even lossy audio will be made even more lossy by codec-dependent compression. My reference solid-state was the SMSL SH-X and for tubes, I used the Feliks Audio Euforia Evo. In terms of headphones, I stuck to my trusty HD6XX, ZMF Auteur Classic, DCA Noire X, and Yanyin Carmen for IEMs. Imaging and phantom stage were checked on FiiO SP3 desktop speakers.

Before I continue, I need to come clean and say that I’m a sucker for R2R sound. This year one of my highlights was the FiiO K11 R2R which is a terrific way for everyone to get infected. I like the realism that most R2R implementations deliver and don’t mind the slight hit overall technicalities. To me, R2R sounds more like music than most ESS and AKM implementations I come across nowadays. With that said, I have to admit that delta-sigma DACs have grown tremendously in the last 10 years.

The review continues on the second page. Click here or use the jumps below.