Apple MA261Z/A User Manual - Page 599

VIII If you set the reference level of the Final Cut Express HD floating audio meter to -20 dBFS, you have nearly 20 dB of headroom, since 0 dBFS is the digital limit for the loudest sound. If you set the reference level in your sequence to -12 dBFS instead, you have less headroom. Even though the average level of your audio is higher, there won't be as much dynamic range. 0 -6 -12 -18 -24 -36 -48 -66 -∞ Available headroom with a reference level of -12 dBFS How much dynamic range you allow in your audio mix depends on its ultimate destination. If you're editing a program for TV broadcast, a reference level of -12 dBFS is fine, since you are only allowed 6 dB of dynamic range anyway. But if you're working on a production to be shown in movie theaters, consider using a reference level closer to -18 or even -20 dBFS (both of these are frequently used standards). Remember that the ultimate goal is to ensure that audio doesn't peak over 0 dBFS in your mix (as displayed in the Final Cut Express HD audio meters) and won't peak over +3 dB or so on an analog meter. Final Cut Express HD Generic audio meters VU meter +7 0 +4 -6 +2 0 -12 -2 -18 -4 -24 -7 -36 -10 -48 -20 -66 -30 -∞ 6 dB of digital overhead does not equal 6 dB of analog overhead. It's closer to 3 dB of analog overhead. Chapter 43 Audio Levels, Meters, and Output Channels 599