Bricasti M3 Network Attached DAC Lab Report

Lab Report

In the nine years since we tested the original Bricasti M1 [HFN Jun '11] and then the 'Gold Edition' [HFN Oct '16] the design has evidently been 'finessed' to the point where this more affordable M3 version could be derived, complete with custom DSD DAC and headphone amplifier. For LPCM inputs the same Analog Devices AD1955A DACs still define the very low 0.00016% distortion through the midrange at its (fixed) 4.0V peak output, falling to 0.00007% at –10dBFs and 0.00025% at –30dBFs [see Graph 1, below]. As before, there's a slight increase in 3rd harmonic distortion to 0.0017% at 20kHz falling to 0.00035% between –10dBFs and –30dBFs (a function of the analogue stage) while the A-wtd S/N ratio is boosted by a few dB to 114.5dB and low-level resolution also improved to ±0.1dB over a full 100dB dynamic range.

Bricasti's DDS (Direct Digital synthesis) clocking is retained for the M3 but jitter is not as vanishingly low as it was in the M1. Numerically high at 1915psec, the specific jitter sidebands are nevertheless very low rate at ±15Hz, ±25Hz, ±35Hz and ±45Hz, so the subjective impact will be reduced. Bricasti has elected to offer both linear and minimum phase digital filters as part of its integral 8x upsampling regime [Graph 2, below]. It specifically recommends not upsampling data in an upstream media player/server but to deliver the files in native form to the M3. Both filters offer the same 105dB stopband (image) rejection and very similar response curves that reach –0.15dB/20kHz with 48kHz media and rolls steeply away beyond –3dB/36kHz (96kHz files) and –3dB/60kHz (192kHz files). These engineered roll-offs are earlier than typical but are not inherently 'wrong'. PM


Distortion versus 24-bit digital signal level over a 120dB range at 1kHz (black) and 20kHz (blue)


Time (linear phase filter, black; minimum phase filter, red) and magnitude responses at 48kFs (black), 96kFs (red) and 192kFs (green)

Max. output (<1% THD, DAC/Pre) 3.99Vrms at 42ohm
Max. output (<1% THD, headphone) 8.8V/600ohm / 845mW/25ohm
Headphone output impedance 315-650mohm (20Hz-20kHz)
A-wtd S/N (S/PDIF / USB / headph.) 114.5dB / 114.4dB / 116.3dB
Dist. (20Hz-20kHz, DAC/headph.) 0.00016-0.0017%/0.00025-0.0016%
Freq. resp. (20kHz/40kHz/80kHz) +0.0dB to -0.14dB/ -16dB / -24dB
Digital jitter (48kHz/96kHz) 1915psec / 1705psec
Power consumption 27W
Dimensions (WHD) / Weight 356x57x286mm / 4.5kg
Price £5399-£6999

Bricasti Design Ltd
Supplied by: SCV Distribution, Hertfordshire
03301 222500