DS Audio Grand Master Cartridge Lab Report

Lab Report

There are clear parallels between the performance of the Grand Master flagship, its predecessor the Master 1 [HFN Dec '17], the DS-002 [HFN Jun '17] and DS-W2 [HFN Jan '19] but the stiffer diamond cantilever, reduced moving mass and dual-mono LEDs/photocells within the GM clearly benefit its performance. The 2V output (1kHz/5cm/sec) is a function of the equaliser as are the six tailored 'bass contours', three rolling off from a notional 50Hz and three from a lower 30Hz. Output A gives the strongest bass in both 30Hz/50Hz settings [black/grey traces, Graph 1], the former's +4.3dB/20Hz boost similar to the default response of earlier DS pick-ups. Output B/50Hz [dashed grey trace] gives the flattest bass with Output C/50Hz (–5.6dB/20Hz) proving the 'safest' with big, reflex-loaded speakers.

However, it's the boosted and extended HF response of +3.4dB/20kHz that marks out the GM as the most advanced DS Audio pick-up to date – its extended bandwidth also reflected in the 9% THD peak being pushed out from ~7kHz to 10kHz here [see Graph 2, below]. The dual photocells increase midband stereo separation by ~5dB to 34dB while the diamond stylus/cantilever combination offers a more accurate 22o VTA. Compliance is 'stiffer' at 11cu but bodyweight slightly lower at 7.7g so the GM is arguably more compatible with mid/heavy effective mass arms. Finally, while downforce is increased to 2.1g, the GM gains little in tracking security, clearing the 75µm groove pitch (65µm on the left channel), but not making it to 80µm. PM


Frequency response (–8dB re. 5cm/sec) lateral (L+R, black, Output A/30Hz; dashed, o/p B; dotted, o/p C; grey, o/p A/50Hz; dashed, o/p B; dotted, o/p C) versus vertical (L–R, red, Output A/30Hz)


Lateral (L+R, black infill) and vertical (L–R, red) tracing and generator distortion (2nd-4th harmonics) vs. frequency from 20Hz-20kHz (–8dB re. 5cm/sec)

Generator type/weight Photo-optical / 7.7g
Recommended tracking force 2.0-2.2mN (2.1mN)
Sensitivity/balance (re. 5cm/sec) 2050mV / 0.30dB (from Eq unit)
Compliance (vertical/lateral) 11cu / 15cu
Vertical tracking angle 22 degrees
L/R Tracking ability 65μm / 80μm
L/R Distortion (–8dB, 20Hz-20kHz) 0.60–8.8% / 0.33–9.2%
L/R Frequency resp. (20Hz-20kHz) +4.0 to –0.5dB / +4.5 to –0.4dB
Stereo separation (1kHz / 20kHz) 34dB / 25dB
Prices £11,995/£38,000 (cartridge/PSU & equaliser)

Digital Stream Corporation
Kanagawa, Japan
Supplied by: Soundfowndations Ltd, Berks
0118 9814238