A.3 Performance Specification
The following pages contain audio performance specification figures for the
A.3.1 Measurement Conditions
For each set of figures on the following pages, the specific unit and test setup will be stated at the beginning of that section. Any changes to the specified setup for any particular figure(s) will be detailed beside the figures to which that difference applies.
A.3.2 Measurement References
Unless otherwise specified the references used in this specification are as follows:
• | Reference frequency: | 1kHz |
• | Reference level: | 0dBu, where 0dBu ≈ 0.775V into any load |
• Source impedance of Test Set: | 50Ω | |
• Input impedance of Test Set: | 100kΩ | |
•All unweighted measurements are specified as 22Hz to 22kHz band limited RMS and are expressed in units of dBu
•All distortion measurements are specified with a 36dB/Octave low pass filter at 80kHz and are expressed as a percentage
•The onset of clipping (for headroom measurements) should be taken as 1% THD
•Unless otherwise quoted all figures have a tolerance of ±0.5dB or 5%
•All measurements are made with the operating level switch set for +4dBu
A.3.3 Microphone Amplifier Performance
Signal applied to Microphone Input and measured at Output. Pad switched out and Input Gain control set to +12dB (minimum).
Gain | Continously variable from +12dB to +75dB |
| Independently switchable 20dB Pad available |
Input Impedance | Continously variable from ≈1k2Ω to ≈10kΩ |
Output Headroom | > +26dBu at onset of clipping |
THD + Noise | < 0.003% at 1kHz |
< 0.006% at 10kHz | |
Frequency Response | |
| |
Equivalent Input Noise | < |
(input terminated with 150Ω) | < |
Common Mode Rejection | > 75dB from 50Hz to 1kHz |
> 70dB at 10kHz |
