This professional-grade deck featured balanced XLR analogue connections, alongside both AES/EBU and coaxial IEC958 digital inputs and outputs, as well as an RS422 9-pin serial interface for integration into larger studio systems. The machine included a table of contents function and allowed for the recording of up to 50 characters of text data, facilitating easier track identification during playback.
While the core transport operated similarly to other professional DAT recorders, the Pioneer D-9601’s unique selling point was its high-sampling-rate capability, which required a trade-off in recording time, halving the duration available on a standard cassette. The unit also incorporated a double-speed copy mode, allowing users to clone standard-rate tapes in half the usual time when two units were linked, a feature that proved valuable in busy studio environments where backup efficiency was paramount.
Extended Bandwidth and Sonic Character
The primary technical distinction of the Pioneer D-9601 was its ability to operate at sample rates of 88.2kHz or 96kHz, compared to the conventional 44.1kHz or 48kHz standards. This increase in sampling rate was designed to mitigate the side effects associated with the steep filtering required in standard digital systems, potentially offering a more natural presentation of high-frequency content.
Listeners and engineers noted that while the difference was subtle on routine material, the high-sampling-rate mode often imparted a sense of greater openness and comfort to the stereo image. The upper harmonics were described as having increased clarity and definition, contributing to a more live performance feel, particularly when recording sources with broad frequency responses such as classical instruments or vocals.
1-Bit Converters
The machine employed 1-bit pulse-flow digital-to-analogue converters and linear 1-bit analogue-to-digital converters, supported by stable clock circuitry designed to suppress directional swing in the clock signal axis. When comparing the high-sampling-rate output against standard-rate reproduction, the distinction was apparent to those who A/B tested the sources.
The extended bandwidth was not merely a theoretical advantage; it provided a tangible sonic difference that many professionals found significant, particularly for archival purposes or for material intended for future high-resolution formats. However, for routine CD manufacture, where the final destination was a standard 44.1kHz format, the practical advantage of recording at the higher rate was less clear, as the benefits were not fully realised until a corresponding high-sampling-rate consumer format became available.
Interfacing, Control, and Practical Utility
Beyond its sonic capabilities, the Pioneer D-9601 offered a robust suite of professional interfacing options. The rear panel featured balanced XLR analogue connections, with pin 2 designated as hot, alongside AES/EBU and IEC958 digital ports. An RS-422 interface allowed for control via Sony 9-pin or ES-Bus protocols, facilitating integration into editing and synchronisation systems. The unit also included an 8-pin DIN jack for hard-wired remote control, although a full-function infrared wireless remote was supplied as standard. DIP switches on the rear panel enabled users to customise various parameters, including the selection of analogue input and output levels (-10dB or +4dB) and the configuration of the serial control protocol.
Easy downsampling
A particularly useful feature was the sampling down-conversion function. By adjusting the rear-panel DIP switches, the digital output could be down-converted from 96kHz to 48kHz or from 88.2kHz to 44.1kHz using a decimation filter. This allowed high-sampling-rate masters to be easily copied to standard-rate equipment without introducing further degradation, ensuring that the down-converted signal sounded identical to a simultaneous standard-rate recording. The X2COPY mode further enhanced efficiency by enabling digital copies of standard-rate tapes to be made at double speed when two Pioneer D-9601 units were linked. This feature was highly regarded in studio environments where time was a critical factor in backup and duplication tasks.