Technics SL-P3 CD Player Lab Report

Lab Report

Largely its own design, including the 'SRLP007N01A' optical mechanism, Technics' only significant deviation from the 'Matsushita chipset cookbook' is its use of a single Burr-Brown PCM53JP-V DAC. Hitachi used the same in its inaugural DA-1000 [HFN Sep '16] as did B&O in its CD50 [HFN May '15], albeit with 2x oversampling. A little later, Sony used a pair of these 16-bit DACs in its CDP-502ESII player [HFN Nov '21] together with its own CX23034 2x oversampling filter to form what it described as its 'Unilinear Converter System'. Technics' application here is more basic, but with its own spin in addressing the interchannel phase shift associated with the use of a single monolithic DAC, time-shared between L/R channels.

Its analogue low-pass filtering is less aggressive than Hitachi's (–41dB vs. –94dB at 24kHz re. 20kHz) but the ±0.25dB ripple at the top-end of its response [see Graph 2] is unchanged. The player has a slightly low 1.9V output from a 285ohm source impedance, and is phase-inverting [see impulse, Graph 2] but the 99.6dB A-wtd S/N ratio is still good for the era. However, while this suggests a 16-bit+ resolution, in practice there's a boost given to low-level detail – signals at –80dBFs are +1.7dB 'louder' and those at –90dBFs are up by +3dB, suggesting a resolution of ~15.5-bits is nearer the mark. Distortion is low at 0.0015-0.004% (re. 20Hz-20kHz/0dBFs) and typically lower at high frequencies [see blue infill, Graph 1] as Technics' analogue filter also removes distortion harmonics >20kHz. There's also a freedom from the ultrasonic noise we might encounter today from modern delta-sigma/noise-shaping DACs. Also, as we saw in the Hitachi DA-1000, jitter is mainly data-induced and, frankly, impressively low at 550psec for an early second-generation player. PM

1022vint.lab1

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

1022vint.lab2

Time domain (note phase inversion) and frequency responses on expanded scale (±0.25dB/div)

Maximum output level / Impedance 1.90Vrms / 285ohm
A-wtd S/N ratio 99.6dB
Distortion (1kHz, 0dBFs/–30dBFs) 0.0014% / 0.031%
Distortion & Noise (20kHz, 0dBFs/–30dBFs) 0.0035% / 0.0015%
Frequency response (20Hz-20kHz) –0.01 to +0.33dB
Digital jitter (Left / Right) 555psec / 1140psec
Resolution @ –90dB/–100dB +3.1dB / +2.7dB
Power consumption 19W
Dimensions (WHD) / Weight 430x82x334mm / 5.3kg
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