Every once in a while I get a little carried away with trying to think up some technical gem; this time, for a change, I thought it might be nice to take things back to basics – real basics – but not necessarily real simple. Sure, it’s good to know the “hows” (how to do this and that), but more importantly it is better to know the “whys.”
We all know (in digital) that the green lights on the record level meters are good and the red lights are BAD. Did you know however that there are different shades of red? Okay, well there aren’t really, but some nasty red lights on tracks are more acceptable than others…
Of course, we could simply avoid any red lights at all (and the point of this article) by setting levels really low; so why not be extra conservative when setting record levels? The reason we are trying to maximize levels is two-fold; both reasons having to do with noise. There is an inherent noise floor in a preamp that the microphone is plugged into; there is also a noise floor is present in the analog to digital converter that the preamp is plugged into. The A to D conversion process also suffers from a different type of noise, “quantization noise,” that can become an issue when recording digitally at low levels. The noise floor of a preamp or A to D converter can be heard as a hiss; whereas quantization noise is more of a digital artifact that is present when an instrument being recorded is so quiet that it is barely moving the meters. So, in an ideal world we are simply trying to get our recorded signal as loud as possible above the noise floor of the electronic circuits and digital conversion process.
Life isn’t always so simple though is it? It turns out that many mic preamps, especially the tube variety, have a “sweet spot.” There are often three amplification or electronic stages on the way from a microphone to a digital recording medium. The first stage can be found in the microphone itself. A condenser microphone will often have a “pad” where you can attenuate the volume of the incoming signal. If you find your source sounds distorted no matter how low the preamp is set, your source could be distorting your microphone.
The next amplification stage is the mic preamp. This is usually the piece of gear where you get to trust your eyes AND ears. Many mic preamps have little red lights to tell you whether they are distorting or not; sometimes a little red light on the mic-pre can make the track sound more aggressive or fatter; be very careful with this though as there is no “undo” button for a distorted signal. You might find you can add a bit of “grit” later in the digital plug-in world.
Don’t be afraid to trust your ears; no you don’t want lots of little red lights in your digital recordings, but don’t go stopping a take if “the magic is happening” and your ears say it’s okay. It is probably much better to have a flawed recording of a great performance than a technically perfect recording of something completely unremarkable (Hmmm, I am suddenly thinking of some people’s records…).
Alec Watson is a producer engineer that works from his destination studio sitting atop the Georgia Strait – not to be confused with George Straight. Visit him online at www.alecwatson.com.