Analogue v.s. Digital: Limiters for Recording Sound
On this video by our colleague photographer and videographer Curtis Judd, we look at a technical subject in audio recording – the difference between a built in analogue limiter and a digital one.
Let’s make things clear from the start – most if not all consumer level sound recorders (even the somewhat more expensive ones at close to or around $1000) have digital limiters. So for the sake of this video we can assume that unless you are going to do a very high end video/audio project or you have very deep pockets and just enjoy spending money on high end audio recorders – you will likely always use recorders with digital limiters (one exception might be renting high end pro level gear for a project).
So with that out of the way – we are looking – for the most part, at a theoretical interest for most users (nothing wrong with that). So to satisfy your curiosity – a limiter is used to prevent the recorded sound from getting too laud (basically above 0db). This can be done either before the sound is converted to a digital signal (zeros and ones) – which means that we are dealing with an analogue limiter or more commonly as we noted – right after the conversion as a digital limiter.
A digital limiter is a piece of software which does the compression automatically when you turn the limiter on. An analogue limiter is a hardware component and this is why it is used in much more expensive gear. An analogue limiter has more of a chance to salvage sound which is getting too laud during the recording.
By the way – in an interesting answer to a question about the importance of both Analogue and Digital limiters made to this video on YouTube Judd stated this: “I think that there is a place for both analogue and digital limiters. In fact, the SD 633 has both. Analogue is most critical for preventing clipping WHILE recording as demonstrated here. Digital limiters are great in post when you’re not dealing so much with audio that is already clipped, but to prevent clipped audio as a result of processing. There’s definitely a place for both.”
We do want to mention that most modern recorders also include the option to perform a dual recording at reduced levels so that in case you will run into very high sound you will always be able to use the second – lower – recording (certainly worth using – we have used that during several interviews that we did in Photokina where the sound level in the area was very noisy and unpredictable).
Bonus video: how to record with any mic to your computer with a Zoom recorder
You can check out more of Judd’s videos which focus mostly on audio and video here on LensVid finally if you are into sound recording for video productions check out this link which covers both equipment and techniques here on LensVid.