CD Player/Transport Reviews

The four transports held in highest sonic regard (the Mark Levinson No.31, the C.E.C. TL 1, the PS Audio Lambda, and the Proceed PDT 3) all had low jitter. I thought the PS Audio Lambda was slightly better-sounding than the PDT 3——and the Lambda had slightly lower jitter.

Fig.1 is the PS Audio Lambda's jitter spectrum with digital silence (track 4 on the CBS Test CD), the heavy dotted trace is the jitter spectrum when the transport is transmitting a –90dB, 1kHz sinewave, and the lightest (top) trace is made with a 1kHz, 0dB sinewave. The RMS jitter level was 51ps (worst case) and 29ps (best case). The musical signals produced the jitter plots in fig.2, which had RMS jitter values of 66ps (Firebird) and 37ps (Steve Morse). Note how the low-level musical source produced more jitter than the high-level one. The Lambda is representative of a transport with very good S/PDIF jitter performance.—Robert Harley