Douglas Spotted Eagle |
May 7th, 2006 12:09 PM |
Quote:
Originally Posted by Fred Retread
Strictly speaking you could say that's true, and there are other applications for limiting output level. For videographers though, the reason is almost invariably to prevent clipping, and the limiters marketed to us for that purpose do not themselves clip, flatten, fold, bend, staple or mutilate audio signals to any significant degree, including pure sine waves, when operated within their design range. That would be absurd. That's the door I came in.
|
Limiters marketed to any market do indeed fold, spindle, mutilate, bend, whatever, because that's exactly what they're designed to do. They're not designed to prevent clipping, they're designed to hold a specific level at all times. There is no "videographer's limiter" and a "studio engineer's limiter" etc. They're all the same, just used differently in various contexts. I'd never use a really hard limit when recording a bit of dialog, I'd prefer to use softer compression starting earlier, because I don't like recording hard limits unless that's really, really, called for. If you record this way, you're married to it for ever. If you've got a dialogic that calls for extreme measures, then you'll want a compressor prior to the limiter so it's not quite so harsh. BTW, a limiter is just a compressor with more strict behavior. It's like a parent to the compressor's child.
Maybe you want a hard limit at 0dB, and you're feeding it +9 in the analog world. Perhaps you want it to limit at -6dBfs, and you're feeding it -2dBfs. You're going to get two extremely different results and audio qualities from both of those scenarios. Limiters have nothing to do with distortion overall, and they'll distort the signal by their very existence. You're associating "distortion"="bad" when in truth, distortion is anything that changes the paramaters of the audio from its orginal dynamic form. Color correction "distorts" the original image the eye sees, but it likely (hopefully) is a pleasing distortion.
If you're feeding the limiter a very dynamic signal, it may prevent truncation of the signal, but the waveform is still flattened out much like a truncated waveform due to the ceiling placed by the limiter. That will present itself audibly, as "distortion" because of the way your ear will respond. But it's not truncated. It can actually be somewhat repaired in post to make it more ear-palatable, where truncated audio really can't be.
Either way, it seems the thread is pretty far off track at this point.
|