5 Replies Latest reply on Sep 9, 2009 12:16 PM by Jim_Simon

    One for the developers

    AMTN

      How the audio is calibrated and displayed in Premier is ok for domestic or maybe semi-pro set ups but the professional broadcast world works very differently.What I mean is this.

       

      Within the individual audio tracks in Premier, 0dBs sits only 6dBs below the absolute maximum possible signal level. On the Master output fader 0dBs is the maximum possible output level. Therefore, within Premier, the degree of headroom is only 6dBs. But professional broadcast specifications require a much greater degree of headroom than this.

       

      For Sony and Panasonic professional decks the headroom is in the region of +18dBs. So our maximum permissable level, or what shows as 0dBs on the meters of a Sony HDCam deck sits at -18dBs on the level displays within Premier. And this is for audio that has been processed or 'mixed' as we call it.

       

      When we shoot in the field, because the cameras dont have built in compressors or peak level limiters, we record our audio even lower than that to avoid the possibility of clipping. So a recorded interview will sit around -26dBs when captured in Premier.

       

      The result of this in our daily lives is that the audio wave forms in Premier dont really work. A recorded interview is barely visible in the waveform view. This is quite a headache because, as anybody who has a lot of experience editing will tell you, we cut by audio first. If video cant follow we will split the video edit rather. So audio playback is actually more important in some respects than picture.

       

      In a perfect world we should be able to calibrate the audio meters in Premier. People like Pinnacle and Avid dont have this problem because they supply their own hardware. So 0dBs on their metering actually appears as 0dBs on the decks metering. You have a much better indication of where you are and how high you're audio levels are in the real world. Avid found this still wasn't enough and gave us the ability to adjust the height of the waveform within the track. Then you can really see what you are doing.

       

      Otherwise, keep it up guys, you are doing a good job.