Audio Engineering

Digital Audio Production 595

20.1.1 Hard-Disk Editing

Not long ago, most recordings were mastered on two-track analogue tape. Whether the
performance was by a soloist, small classical or rock ensemble, or full orchestra, the good
“ takes ” of a recording session were separated from the bad and joined together using

Table 20.1 Audio subsystem specifi cation for onyx and CHALLENGE

Number of channels 4 analogue (16 bit), 2 digital (24 bit)

Input analogue route

Input Z 20 k ohms

Input amplitude From 0.63 V pp to 8.4 V pp for full-scale modulation (this level is

adjustable under software control)

Frequency response 0.81 dB 20 Hz to 20 kHz

THD  noise Less than 0.007% 20 Hz to 20 kHz

Residual noise –86 dB unweighted

Cross talk –82 dB at 1 kHz, –67 dB at 20 kHz

ADC type 16-bit Delta-Sigma

Output analogue route

Output Z 600 ohms

Output level 4.7 V pp (4.4 dBV) for 0 dBFS

Sampling rates 32, 44.1, 48 kHz, or divisors selectable

Frequency response 1.2 dB 20 Hz to 20 kHz

THD  noise Less than 0.02% 20 Hz to 20 kHz

Residual noise –81 dB unweighted

Cross talk –80 dB at 1 kHz, –71 dB at 20 kHz

Digital serial I/O

Type Coaxial only

Input Z 75 ohms, transformer coupled

Input level 0.5 V pp into 75 ohms

Sample rates 30 kHz to 50 kHz

Output Z 75 ohms, transformer coupled

Output level 0.5 V when terminated in 75 ohms

Coding AES-3, IEC 958