dCS Bartók Network DAC/Headphone Amp Lab Report

Lab Report

While the Bartók's Ring DAC/analogue output is based on the Vivaldi One [HFN Feb '18], the latter still has the slightest edge in terms of distortion (0.00009% vs. 0.00015% at –10dBFs) and A-wtd S/N ratio (117dB vs. 116dB). However, the former bests the flagship in terms of jitter: both units show a minuscule correlated jitter of <10psec at all sample rates but the Bartók has eliminated the very slight uncorrelated phase noise we saw with the Vivaldi One. In market context, both units represent the state-of-the-art in technical performance.

719bartok.lab1

THD vs. digital signal level at 1kHz (red, line out; black, headphone out into 25ohm) and 20kHz (cyan, line out; purple, headphone out into 25ohm)

719bartok.lab3

Time/frequency responses with 192Hz data (filters 1-6 = black, red, cyan, orange, green, purple)

The Vivaldi's six custom digital filters are also shared by the Bartók, all offering a flat 20Hz-20kHz response (±0.05dB) with CD inputs. Filter 5 is the only minimum phase type, and similar to Filter 6 for 192kHz data [purple impulse and response, Graph 2]. The 'NOS' Gaussian Filter 5 is reserved for >96kHz sample rates [green traces] while Filters 1-4 are linear phase for all rates [black, red, cyan and orange]. DSD Filters 1 and 2 reach out to –8.5dB and –21dB/100kHz, respectively, while Filter 3 rolls off to –3dB/60kHz and –23dB/80kHz. The DSD Filter 4 is –0.7dB/20kHz and –6dB/30kHz before dropping steeply at 40kHz.

The partnering Class A headphone amp matches the XLR output's 600mohm source impedance with sufficient current to support 1.7W/25ohm. Unlike most DAC/headphone amps, the Bartók does not clip at 0dB volume with a peak level digital input, suggesting its potential maximum power output is higher than 1.7W/25ohm. Distortion increases very slightly under load over the top 10-15dB of its dynamic range, from 0.00005% to 0.0016% at 1kHz/0dBFs [red vs. black traces, Graph 1] and from 0.00025% to 0.032% at 20kHz/0dBFs [cyan vs. purple traces]. PM

Maximum output (re. 0dBFs into 47kohm) 5.9V (balanced line out)
Max. power output (re. 0dBFs into 25ohm) 1715mW (headphone out)
Output Imp. (20Hz-20kHz, line/headph.) 0.50-0.71ohm/0.61-0.82ohm
A-wtd S/N ratio (0dBFs; re. 6V/10mW) 116.0dB / 115.0dB
Distortion (20Hz-20kHz, re. 0dBFs) 0.00005–0.00025%
Freq. resp. (20Hz-20kHz/45kHz/90kHz) +0.0 to –0.0dB/–0.7dB/–7.3dB
Digital jitter (48kHz/96kHz) <10psec / <10psec
Power consumption 33W (21W standby)
Dimensions (WHD) / Weight 444x115x430mm / 16.7kg
Price £11,999
COMPANY INFO
Data Conversion Systems Ltd
Cambs
Supplied by: dCS Ltd
01954 233950
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