An Overview of Setting Audio Levels, Part 1

Setting levels on your audio interface and through your DAW isn’t hard. Neither is setting levels on plug-ins, especially ours. But there are a few things to know, so let’s get going.

On the Input

The signal coming out of a mic and into a preamp, and through the preamp and into an interface is actual electricity. This is an analog signal and is subject to the rules of setting analog gain.

The basic rule of setting analog gain is to set it as high as possible and leave a little headroom for natural variations in signal level. We want it as high as possible because almost all the noise (the hiss, the hum, etc.) of whatever you’re recording is going to be introduced into your recording at this point, and we want that stuff as quiet as possible. Some people think hiss and hum are part of the whole “analog vibe” and are charming, but they’re wrong. Back in the old days, we spent a ton of time trying to get rid of that stuff. It’s crap. It’s like the cook's hair on your pizza.

We want to leave some headroom because musicians tend to play or sing a little louder in actual performance—often the performance is 3dB louder than the rehearsal—and we don’t want to add extra harmonics and, even worse, harmonic and intermodulation distortion to our signal unless we’re looking for that sort of sound deliberately.

So, where do we set things? It depends on the meter on the analog device, but generally, there is a 0 point on the meter, be it a VU or an LED bar display, and you want the signal around that zero point. It can go over occasionally. If there’s Peak indicator light, that can occasionally flash red—this is fine. Most meters show green and transition to red when your signal is in the headroom area. Keep the signal high in the green and just licking the red.

It is that easy. As you know more and learn more you can make it more complicated for yourself, but it is that easy. Because it’s easy, though, that doesn’t mean you want to fluff your way through this not paying attention. If you do this step badly you’ll make a lot of problems for yourself. Take the time to set the levels correctly.

So, your properly set signal flows through your analog gear and into your interface, where it gets converted into numbers—math—and feeds into your DAW, and now we have to think of it a little differently.

In the DAW

Most up-to-date, modern DAWS process signals using floating point math. What does this mean? It means that it is virtually impossible to  crank things up too high in the DAW. You can basically set your levels anywhere and it won’t cause “bad math.” However, it doesn’t mean that you can do whatever the heck you want.

Most plug-in, ours included, are designed to emulate analog circuits, and that means that they will emulate distortion and potentially sound like ass if you hit them too hard. Hit them too hard with what? Numbers? There’s no actual electricity feeding through the DAW like there is feeding through an analog recording console. What possibly hits them too hard? Numbers?

Uhm... kind of. If a plug-in is designed to emulate an analog circuit, then it will have a pre-programmed spot in it that emulates the “sweet spot” of an analog circuit, and if the signal is too low or too high for that sweet spot, the plug-in will do some math to add distortion and other non-linearities to your signal. You can’t really overload a plug-in, but you can force it to emulate an overload. This is something you can choose to do, but you need to understand something to actually choose it.

So, how do you know if you’re overloading a plug-n or operating it out of the sweet spot. Well, if it sounds all distorted and, as far as you can tell, it isn’t supposed to sound all distorted, that’s a pretty good indicator. The other thing to do is to look at the damn meters on the plug-in.

Korneff Plug-in Metering

Our plug-ins have two different meters. The PSC, TBL, AIP, MDR, ETD, and Puff Puff all have a meter that looks something like this:

We will be changing this meter on these plug-ins soon, but to set the level using these, you want to see that meter as close to the 0dB line as possible without going over it very often. You’re basically setting it the same way you’d set a piece of analog equipment, which makes sense because it’s designed to emulate analog equipment. If you set it too low you might hear some weirdness. If you set it too high you might hear some distortions.

Our newer plug-ins, the WOW Thing, and the Pumpkin Spice, have a different meter:

It’s similar but with the addition of a numerical display that shows you how far your signal is from hitting 0dBFS, or Zero Decibels Full Scale.

What the heck is 0dBFS? That’s a really good question, because it’s rather arbitrary. Basically, it indicates when you’ve used up all of the bits available for doing mathy stuff in your DAW, but because DAWs use floating point math, there are always extra bits lying around. Kind of.

Argh! What’s important about 0dBFS isn’t what it is, but how far away you are from hitting it.

Because digital recording gear does have to integrate with analog recording gear, and because digital recording technique is built upon analog recording technique, the “industry” has decided that keeping digital levels somewhere between -20dBFS and -12dBFS is where you want to set things. -18dBFS is sometimes quoted as an exact value. And this isn’t a bad idea at all, especially as you learn about the details involved in the making of the decision.

DAW makers, interface designers, and plug-in makers all use this number. -18dBFS is the level that puts things in “the sweet spot.” If you go above it, you could cause the plug-in to emulate analog distortion.

So, that number on the meter that keeps changing as the signal changes is telling you if you’re hanging around in that sweet spot, from about -20 to -12dB below 0dBFS. Our plug-ins are designed to behave like a nice, happy analog circuit in that area. If you go too high, it might distort. If it sounds bad, turn the Input Trim down.

Use the Output Trim to make sure you’re not slamming too much “digital gain” into the next plug-in. But even if you are, chances are the next plug-in in the signal chain also has a trim control which you can turn down to get the signal into the sweet spot for that plug-in.

I have heard of people sticking meters in between individual plug-ins to make sure things are really close to that -18dBFS value. You don’t have to do this. The whole thing isn’t that anal, and it isn’t rocket science for you, making a record. The rocket science is happening in the DAW and in the plug-ins, so relax.

On the Output

You’re mixing and your individual channels are flowing into submasters most likely, and then into your master bus, and then from there out into a file of some sort—like a .wav or .mp3—and into your monitoring system and into your speakers. And this is another spot where you can cause yourself problems. What kind of problems? Finished recordings that are too quiet because... have you heard? There’s a loudness war going on. And finished recordings that are distorted.

But this is a long discussion and it deserves its own post, which I’m in the process of writing.