Compressor Times

I am frequently frustrated with the default compressor settings on many digital consoles. I have NO IDEA where they come up with some of these, and it’s infuriating for me because I see so many developing engineers get sidelined in really learning how to use compression because the default settings on the console’s compressor don’t set newer engineers up for any kind of success. They see those settings, and it throws them off. They start thinking, “Wait? Is that around where I’m supposed to set this thing?”

Now, don’t get me wrong. A manufacturer isn’t at fault if someone doesn’t know how to properly use a fundamental piece of equipment of audio processing like a compressor. The guy turning the knobs is responsible for what’s coming out of the speakers. However, I get frustrated because those defaults aren’t helping when they very easily could.

So there are two things I see engineers get hung up with in regards to compressor settings. First, the Attack time is just not right. Sometimes it’s way too fast, but more often I see them way too slow these days. Second, I see Release times that are way too long.

Let me just add a caveat here before I get into this in that you really shouldn’t be worrying about specific numbers in terms of times. I’ve written about this before, and the reality is there’s no way to tell exactly what those times really mean. In other words, you can’t take one setting from one compressor and apply it to the same control on another compressor and get the same exact sound because the topologies of how the compressors work are all different. I think you can, however, get in the ballpark, and I say that after jumping between a lot of different consoles and compressors over the last 20+ years. So if I start talking about specific numbers through the rest of this article, don’t think of them in terms of exact numbers. Think of the numbers as ballpark settings.

So what are some good ballpark settings? Well, let’s look at a couple classic compressors to get some ideas. A lot of these units actually have fixed settings internally, and if they are classics that still get a lot of mileage today maybe there’s something to those settings…

Let’s start with the LA-2A. This is a classic compressor and highly regarded for use on vocals. It also gets a lot of use on things like pianos and bass guitars. Funnily enough, I find vocals and bass guitar are probably the two things I compress the most when I’m mixing live.

The LA-2A’s Attack time is program dependent which is something I have yet to to find anyone who can really explain, but the average time is about 10ms. The LA-2A features a multi-stage Release, and the first part of the Release is about 60ms. The second half of the release is much slower, but it’s that first part I want you to focus on: 60ms.

Let’s review a bit: Attack and Release controls are the speed controls for how fast a compressor operates. Attack is how fast the compressor turns things down, and Release is how fast it turns back up. I actually did a video on this a couple years ago which I have embedded below that demonstrates this.

When we have something wildly dynamic like a live vocal, there are a couple things we need. First off, we need a fast-ish Attack time so that the big jumps in level don’t happen faster than our compressor can react because we want our compressor to control and even them out. If we set our Attack too fast, though, we can start losing articulation, dulling the sound, and making our sound seem further away. A 10ms Attack is pretty fast, but not typically so fast that it dulls the source too much so we can usually get a nice balance of clarity and control.

The Release time is sort of the same thing. We need a fast-ish Release time because with something like a live vocal we have words and even syllables within those words that can be wildly different in volume, and we want our compressor to work on those little bits as much as it can. If we go too slow our compressor won’t let go or Release before it can work on the next level jump. On the other hand, if we go too fast on the Release, we can potentially end up distorting our signal or making the compressor pump in a weird way. The thing that makes the LA-2A’s Release so special is we get that 60ms stage for the big swings, but then we have a slower Release that might be a second or longer to more gently ride the signal.

What if you don’t have an LA-2A? Well, I don’t personally have a real LA-2A, but there are a lot of emulations out there these days. I use the Waves CLA-2A, but I’ve also seen LA-2A style emulations built-in to a lot of digital consoles today. Even if you don’t have access to a real LA-2A or emulation, you can still take a page from its design and try a Release time close to 50ms.

Now let’s look at another classic compressor that gets a lot of use on vocals: the 1176. The 1176 actually has an adjustable Release setting with times that go from about 50ms to a second. Guess where most of the engineers I admire set the Release time? Roughly as fast as it will go, which, surprise, surprise is 50ms. Guess where I usually set it? As fast as it will go.

On the Attack side of an 1176, we have times that go from 20 microseconds to 800 microseconds. These are crazy fast Attack times, and most engineers tend to slow that time down to the halfway point or as slow as it can go because, again, if we go too fast we can dull the sound.

So what’s the point I’m trying to make in all this? Well, there’s a couple. First, you really need to learn what exactly your compressor’s Attack and Release settings do to a sound. I’ve got a video up on this and there are others floating around the web, but there’s no substitute for turning the knobs yourself and hearing what they do for yourself. In my opinion, learning to hear Attack is the easiest so I suggest starting there.

Second, you will probably do better at learning these things and get better results with copmression in the meantime if you use a faster Release setting. A good rule of thumb I tell engineers when I’m training is 10 & 100: 10ms Attack and 100ms Release. This is usually a safe ballpark setting to get started, and I wouldn’t be afraid to go faster on the Release on a lot of things because 50ms is common in some classic compressors.

If you really want to dig in on learning about compression and utilizing it in your mixes, it’s a big part of what I teach when I do on-site training. Hit the Contact button on my website because I’d love to connect to talk about how some personalized training may benefit you and your church’s audio team.