Ferguson CD 03 CD player Lab Report

Lab Report

Arguably rarer still than the Ferguson CD 01 player [HFN Jan '19], this CD 03 variant is not a wholesale evolution on the original. Yes, it shares the same CX20017 non-oversampled, time-shared 16-bit DAC as Sony's inaugural CDP-101 [HFN Jan '12], together with a later KSS-121A transport mechanism that reads yet-to-have-been-invented CD-R discs with slick efficiency. However, while the output buffer offers a full 2.1V instead of 2V, and peak level distortion is reduced from 0.00075% to an even lower 0.00034% [black trace, Graph 1 below], the A-wtd S/N ratio is unchanged at 98.4dB and the source impedance is far higher at 1.63-1.76kohm. So the CD 03 will be less cable agnostic than either the CD 01 or any of the early Sony players.

That there's a different analogue filter chip between the DAC and output buffer in the CD 03 is also indicated by its stopband rejection – a figure of 41dB putting the CD 03 far closer to Sony's CDP-101 than the 90dB achieved by the CDP-11S and Ferguson CD 01. That said, the reconstructed response is just fractionally smoother, albeit with a bass lift here, while the impulse response [inset, Graph 2] demonstrates a less aggressive ripple/ringing. As before, the 0.0113msec offset between left (black) and right (red) is a function of the sequential left sample-by-right sample conversion of this 'mono' DAC.

Low level resolution is improved in the CD 03, the boosting of detail at –90dBFs and –100dBFs seen with the CX20017 DAC is just half that recorded for the CD 01 at +3.5dB to +3.8dB, respectively. Jitter was not measurable in 1985 but the CD 03 follows the same mild data-induced pattern we saw in the CD 01, albeit slightly higher in this model at 770psec. In practice this might just as easily be a function of production variation. PM

1119vintage.lab1

Distortion versus 16-bit CD digital signal level over a 120dB range (black = 1kHz; blue = 20kHz

1119vintage.lab2

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

Maximum output level / Impedance 2.10Vrms / 1.63-1.76kohm
A-wtd S/N ratio 98.4dB
Distortion (1kHz, 0dBFs/–30dBFs) 0.00034% / 0.0083%
Distortion & Noise (20kHz, 0dBFs/–30dBFs) 0.0055% / 0.0012%
Frequency response (20Hz-20kHz) +0.15 to –0.36dB
Digital jitter 770psec
Resolution @ –90dB/–100dB +3.5dB / ±3.8dB
Power consumption 7W
Dimensions (WHD) / Weight 354x70x270mm / 6kg
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