CD Player/Transport Reviews

The Cambridge CD player was subjected to a formal sequence of tests. In the lab, a range of tests was applied to explore the linearity and resolution of the machine. Factors such as shock and vibration immunity, error correction, and the like were all investigated. If A/B assessment is to be attempted, it is vital to determine absolute output levels, and it is well worth checking any deviations in frequency response which might affect the auditioning.

The precise bit resolution delivered is at present academic, as we have not yet been able to satisfactorily prove that effective resolutions better than 14.5-bit are audibly superior, in the light of current recorded program quality. Very few players can reach 16-bit at present, and there is little correlation between sound quality and the actual bit resolutions displayed by most of the better players. An engineering examination, however, is still useful, as it can show just how much care has gone into both mechanical and electrical design and build.

The auditioning was carried out on an absolute, single-presentation basis, with a variety of material, as well as by more detailed A/B/A (not switched or instantaneous) comparisons. Care was taken to match absolute levels to ensure fair comparisons.

Where possible, the sound of various CDs was referenced to analog originals using the most neutral vinyl players, namely the Goldmund Studio and the most recent Pink Triangle. Program material included Sheffield Lab recordings from Dave Grusin and James Newton Howard, Paul Simon's Graceland, Vivaldi's Four Seasons on Argo (Marriner/ASM), Miles Davis's Tutu, Joe Cocker's Civilized Man, and the Ashkenazy/London Rachmaninov Symphony 1 recording.

Direct analog vs digital comparisons can be misleading due to differing tonal balances. The subjective analyst, however, must reach beyond this superficial difference and attempt to quantify the musical, as well as the emotional, content of the replay. Factors such as stereo focus and depth, transparency, treble purity, dynamics, and bass definition are key areas of judgment.—Martin Colloms