Many enthusiasts recognise Oppo Digital as a manufacturer of overachieving universal disc players, high performance planar magnetic headphones, and related personal audio electronics. But, over the past year or two, Oppo has begun to explore the wireless audio product category, first through its Sonica-series multi-room wireless speaker systems and now through the audiophile-grade Sonica DAC/network streamer, which is the subject of this review.
I first encountered the Sonica DAC at a trade show late last year, where I had a chance to speak with Oppo’s Chief Technology Officer Jason Liao about the unit. Liao, who is often modest to a fault, carefully outlined the elaborate features and functions of the Sonica DAC and then said, very softly, “I think it’s the best sounding source component Oppo has ever built,” which was saying a mouthful, considering the source. I decided then and there that, pending Editor Sircom’s approval, Hi-Fi+ would have to review the unit once it entered full production to see what it could do.
In trying to understand the Sonica DAC’s capabilities, it helps to start by looking at its primary function, which is to serve as a versatile, audiophile-grade DAC. To fill that brief, the Sonica DAC is based upon ESS Technology’s ES9038PRO 32-bit HyperStream DAC device, which is the flagship of the ESS SABRE PRO-series range and is said to offer a stonking 140dB of dynamic range. The DAC’s USB input supports PCM audio from 44.1 kHz up to 768 kHz with word lengths of 16, 24, or 32-bits; it also converts DSD 64, 128, and 256 in DoP (DSD over PCM) or native format, and can even handle DSD512 in native format. Additionally, the DAC provides connections for USB storage devices, coaxial and optical (Toslink) S/PDIF inputs, plus a host of network streaming inputs, which we will touch upon in a moment. The S/PDIF inputs, network inputs, and USB storage device inputs, support PCM files captured at 44.1 kHz to 192 kHz rates with bit depths of 16 to 24-bits, plus DSD 64 files.
In the interest of achieving high signal purity and low noise, the Sonica DAC provides fully balanced analogue circuitry from end to end (that is, it preserves a balanced circuit topology all the way from the DAC chip on through to the XLR connector-equipped balanced outputs on the rear panel). In fact, Oppo stresses that even the single-ended, RCA jack-equipped outputs rely upon an output signal that is, “converted from the balanced output.” Oppo claims that its balanced circuit design, “provides better common-mode noise rejections, improves signal quality, and results in better channel separation by eliminating the common ground return path.”
Feeding the Sonica’s digital and analogue audio sections is a beefy power supply based upon what Oppo describes as, “a massive toroidal transformer, which offers superior efficiency and significantly lower exterior magnetic field interference compared to traditional laminated steel core transformers.” This helps explain, in part, the fact that while the Sonica DAC is not a physically large unit, it nevertheless tips the scales at a hefty 4.7 kg (a weight exceeding that of some of Oppo’s earlier generation universal disk players). Suffice it to say that when you lift the Sonica DAC from its box, it presents itself with an impressive quality of heft that suggests it is a substantial component in more ways than one.