CS 104 Mixers Application Notes
June 1996
Revised 1, Aug. 1997


Metering Options

VU: Slow rise and fall times. (300 ms, 300 ms)

Peak: Fast rise and slow fall times. (10 ms, 500 ms)

VU meters were designed to indicate the average program level. They are useful for indicating the relative 'loudness' of program material. However, as they do not respond to 'peaks', there is the possibility of overloading the recorder circuitry (peaks can be 8-15 dB higher than the average level). This is not so much of a problem with professional analog audio recorders but with today's digital audio recorders and video cameras, peak levels need to be accurately monitored.

Peak reading meters (on the CS 104 and CS 106 + 1) will fully display peaks of longer than 10 mS. Their ballistics are similar to the Nagra modulometer and the BBC spec for PPM meters (however, with a shorter fall time). The reference tone on the mixer is set a -8 dB below 0, therefore, peaks of 8 dB above the average level will be displayed at 0 dB.

When using a recorder with a VU meter, this tone should still be sent at -8 dB and the recorder input adjusted for 0 VU. The two meters will then react approximately the same to program material.


CS 104 - v.2    
  Meter dial = VU: Tone at 0 vu (full scale +3)
  Meter dial = CSS (peak): Tone at -8 (at the ) (full scale +4)




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