Ferguson CD 01 CD Player Lab Report

Lab Report

This rare Ferguson player shares many of the technical features we uncovered when testing Sony's inaugural CDP-101 [HFN Jan '12], although the donor chassis is Sony's later CDP-11S model which has a less sophisticated power supply. In practice, Ferguson's CD 01 shares the same CX20017 non-oversampled, time-shared 16-bit DAC and final analogue output buffer as the CDP-101, together with the same KSS-100 transport mechanism that, remarkably, reads yet-to-have-been-invented CD-R discs with slick efficiency. The analogue filter chip between the DAC and output buffer has clearly 'evolved' between the CDP-101 and CDP-11S, however, offering an improved stopband rejection of 90dB vs. 39.7dB and a flatter reconstructed response [Graph 2, below] that's within –0.0/+0.2dB through presence and treble, falling to –1dB/20kHz as the steeper filter bites.

319vintage.lab1

Distortion vs. 16-bit CD digital signal level over a 120dB dynamic range (1kHz, black; 20kHz, blue)

319vintage.lab2

No digital filter, so no pre-ringing on the impulse response! Response [above] is broadly flat

Otherwise all is very familiar: the impulse response [Graph 2] shows none of the pre-ringing associated with a linear digital filter – the 0.0113msec offset between left (black) and right (red) a function of the sequential left sample-by-right sample conversion of this 'mono' DAC. Once again, the A-wtd S/N ratio is 2-3dB over the 16-bit standard while its treatment of low-level detail shows some emphasis – signals at –80dBFs are boosted by +3.1dB while those at –90dBFs by a full +6.3dB. Distortion, very low at just 0.0007% through the midrange at peak levels, is actually lower still at high treble frequencies with signal levels below –20dBFs [blue infill, Graph 1, above]. So at –30dBFs distortion is 0.003%/1kHz but just 0.0009% /20kHz, a 'role reversal' that's a feature of the CX20017 DAC. Jitter, meanwhile, was not measurable in 1984 so it's refreshing to discover the CD 01 incurring a respectably low 360psec. PM

Maximum output level / Impedance 2.02Vrms / 419-574ohm
A-wtd S/N ratio 98.6dB
Distortion (1kHz, 0dBFs/–30dBFs) 0.00075% / 0.0032%
Distortion & Noise (20kHz, 0dBFs/–30dBFs) 0.0022% / 0.0009%
Frequency response (20Hz-20kHz) +0.18 to –0.07dB
Digital jitter 365psec
Resolution @ –90dB/–100dB +6.3dB / +7.3dB
Power consumption 16W
Dimensions (WHD) / Weight 354x94x330mm / 6kg
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