Vintage

Conceived in 1985, the XR-V22 was not only a novelty for its twin-tray mechanism but it was also almost entirely an all-Toshiba effort from the transport through to the microprocessor, signal processing and DAC ICs. The latter, a ‘16-bit linear’ TD6705AP chip was also used in early Trio/Kenwood and Onkyo players and is superior to the similarly non-oversampled 14-bit TD6710N ‘low power’ integration-style DAC used a year later in Toshiba’s ‘desktop style’ XR-J9. This is a single-channel, time-shared DAC and so the 22.7µsec interchannel delay and post-ringing caused by the sample-and-hold and analogue filtering, are seen in the time domain impulse alongside the mild –0.2dB presence dip, +0.1dB recovery at 14kHz and final –0.8dB/20kHz roll-off in response [see Graph 2]. Stopband rejection is a modest 28dB (24.1kHz re. 20kHz) but the analogue filter offers greater suppression at higher freqs., squeezing out ‘digital’ 20kHz distortion harmonics caused by quantisation errors – hence the close tracking of 1kHz/20kHz distortion at –20dBFs and below [black/blue traces, Graph 1].

The player’s 2.2V maximum output is useful even if the 1.1kohm source impedance is a little high, and while the A-wtd S/N ratio is around the 16-bit standard at 97dB, the player’s minimal +0.4dB drift in low level resolution at –100dBFs suggests a real-world performance closer to 17-bits. This is excellent for the era even though jitter – a complex pattern based on multiples of ±15Hz – is a little less ‘tidy’. Distortion, meanwhile, falls to a minimum of 0.002% from 20Hz-20kHz over the top 20dB of the player’s dynamic range and peaks at 0.008%/1kHz and 0.01%/20kHz as stress on the (discrete) output stage reaches its maximum at the full 2.2V/0dBFs level. PM

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

Time domain and frequency responses on expanded scale (±0.25dB/div). Note sample offset