dCS Vivaldi One digital media player Lab Report

Comparisons with the full Vivaldi ‘stack’ [HFN Feb ’13] reveal subtle improvements brought about in the evolution of dCS’s signal processing and Ring DAC technology and its integration into this one-box solution. The analogue output buffer still has a fabulously low, cable-agnostic 560mohm source impedance and offers a variable output up to 5.88V. This is perfect for driving power amplifiers directly. The A-wtd S/N ratio is now fractionally higher at 117dB and low-level resolution good to ±0.15dB at –120dB. Distortion is fractionally lower too: down to 0.00001% at –10dBFs and no higher than 0.00009% over the top 30dB of its dynamic range through bass and midrange. At 20kHz distortion falls between 0.0001-0.0004% over the top 30dBFs [see Graph 1, and note the Y scale now expanded from +20 to –140dBFs from –120dBFs]. The only competition faced by the Vivaldi One in technical bragging rights is from Chord’s similarly innovative DAVE DAC [HFN Apr ’16].

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Dist. vs. 48kHz/24-bit digital signal level over a 120dB dynamic range (1kHz, black; 20kHz, blue)

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High resolution jitter spectrum comparing 48kHz/24-bit (red, with markers) and DSD (black)

The proximity of the multiple PSU’s inside the Vivaldi One may account for the minuscule increase in 50/100Hz-related jitter from 10 to 50psec here, while the Ring DAC’s uncorrelated noise ‘skirt’ is also still visible [red spectrum on Graph 2]. Interestingly, both correlated and noise-like jitter are lower via DSD at 22psec [black spectrum]. Frequency responses depend on choice of Filter [see Ringing the Changes sidebar], with Filters 1-4 delivering a ruler-flat ±0.05dB (20Hz-20kHz) with CD media albeit with reduced stopband attentuation (125dB, 35dB, 12dB and 6.1dB, respectively). Filters 5/6 offer a full 125dB stopband rejection with a ±0.04dB response flatness – Filter 5 is a minimum phase type with significant post-ringing and Filter 6 a linear phase type with lower amplitude, but more extended, pre/post ringing. PM

Maximum output level / Impedance: 5.88Vrms / 560mohm (XLR)
A-wtd S/N ratio (LPCM / DSD): 117.0dB / 116.5dB
Distortion (1kHz, 0dBFs/–30dBFs): 0.00005% / 0.00009%
Distortion & Noise (20kHz, 0dBFs/–30dBFs): 0.00024% / 0.00035%
Freq. resp. (20Hz-20kHz/45kHz/90kHz): +0.0 to –0.0dB/–0.7dB/–7.4dB
Digital jitter (48kHz/96kHz / DSD): 50psec / 45psec / 22psec
Resolution @ –100dB/–120dB: ±0.1dB / ±1.5dB
Power consumption: 34W (1W standby)
Dimensions (WHD) / Weight: 444x220x420mm / 27.4kg
Price: £55,000

COMPANY INFO
Data Conversion Systems Ltd
Cambs
Supplied by: dCS Ltd
01954 233950
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