The first dynamic processor I'd like to look at in depth is a gate. Which is also known as a noise gate. And it has that name because, a traditional use of it is to remove the hiss and noise between the important musical moments. If you think of a guitar amp and a guitar player, there's a natural hiss always going on through an amp because they've turned up that drive which also tends to bring up the noise, right? So there's just a hiss going all the time when they stop playing. When they play, it's much louder than the noise. But when they stop, you still notice the noise. And that's what a noise gate is great at. because we can set, with the noise gate, we can set a threshold that's above the noise but below the signal of the guitar. And this way, when the guitar stops playing, the signal of the guitar goes down, and as soon as it crosses a threshold, the gate cuts out all that noise. So, it's a great tool, very useful one, and let's look at it in more depth right now. We're going to first look at gates with kind of a non-musical example. I've created a synth patch that just swells in and then fades out. Let's hear it. [SOUND] Slow swell in and a slow fade out. So that's the sound and I'm curious how we can change that sound with a gate. Now, I'd like to point out the device we're looking at. It's kind of a full featured, dynamics plug-in. And that includes the ability to, to do compression limiting, downward expansion, and gating all in one package. This is very common in contemporary plug-ins, because most of the functionality of all these devices really is the same. It makes sense to put it in one single unit. The first thing we see in this is the Transfer Function. That's the square in the middle of the device. And you'll see this on gates, and compressors. All over the place. This is showing us Input horizontally, and Output vertically. The scale runs from negative 64 decibels full scale, up to zero decibels full scale. Remember the zero DB in full scale is digital maximum and it goes negative down from there. And this is output going vertically, again, from the negative 64 DB up to zero decibels full scale. Right now, because my gate ratio is at 1 to 1, the device is doing absolutely nothing. Now a traditional gate would have a very, very high ratio, meaning it cuts the sound entirely when the sound gets below the threshold. Because we're not running anything through this now, we see the gain reduction meter here is at an extreme. Most devices will have a gain reduction meter. It's showing how much the device is actually acting, how much it's reducing the level at any point. It might be labeled GR and it usually goes down like this, you'll see it on compressors and on gates. Let's hear the sound one more time. [SOUND] For this experiment, I'm going to increase my threshold really, really high. So we're putting it at around negative 10 decibels. So this is saying that anything below negative 10 will be cut dramatically. Let's look at how this transfer function is working. We're saying if the input is negative 48, I don't even see the output, it's so far down. If my input's at negative 32, I don't even see an output, it's so far down. But if my input is at negative 10, the output is also at negative 10. If my input were at negative 5 the output would also be at negative 5. So this line is showing us what the output level will be for every input level, and because we don't see it at negative 32 it's basically silenced. Let's hear what it did to the sound. [SOUND] We see a quick jump and a quick drop as that sound crosses the threshold in both directions. If I was to raise the threshold up, see what happens. [SOUND] We get an even shorter blip because only the very loudest moment is allowed to pass through that gate. Now, let's look at a more musical example. I've added a guitar performance to the song I've been working on earlier, and I like the performance, except there is some noise between the heads and some bigger noises between the heads that I'd like to reduce. So, a gate is a perfect thing to do. First thing, let's hear the part. [MUSIC] It's a pretty nice performance, the timing is how I like it, but there are those little slight finger noises and a little bit of amp noises between the hits and I'd like this to be nice and punchy. So what I need to do is set my gate up. The first thing I'll do is set my gate ratio all the way up, so it is functioning as a gate, and not a downward expander. If I reduce this ratio, the device is working more like a downward expander, and not really like a gate. So I'll put that all the way up. Now I'm going to have to set my threshold, and I'll do it as the song is playing. [MUSIC] And right there we get a great performance. Notice that it reduced the level between each of the hits, creating a much, much cleaner performance. Let's continue on and see what changing a threshold in an incorrect location might give us. [MUSIC] I'm going to keep going higher. [MUSIC] So if I get too high, we notice that the gate starts chattering. And I can even miss some of those important hits. And if I go really too high. [SOUND] I'm just hardly ever going to hear the performance. [SOUND] So you see how that threshold needs to be adjusted perfectly for the input signal. Let's do a little more. [MUSIC]. I think that setting works really well. The final thing I would like to look at in the gate is the impact of attack and release on the gate. Remember attack will be how fast the gate opens up, and release how fast the gate closes down. I like to think of attack and release as referring to the sound itself. Attack is at the beginning of the sound; what does the dynamic processor do? And releases at the end of the sound. I'm going to look at attack first in an experimental way. We'll hit play and listen to the guitar and I'll increase attack and see what it does. [MUSIC]. [MUSIC]. So we see that increasing attack made the gate move slower. It sounded as if the guitar part was swelling in with each hit. As if the guitarist was moving his volume knob on his guitar. Maybe using a pedal of some sort to swell in that sound. Usually, a gates attack is set quite quickly. So those initial transients do come through, and we do hear them. Let's see how release impacts the sound. [MUSIC]. I'll increase release now. [MUSIC]. So we see that with release too high, the gate never really brings the level down fast enough. And we still hear those noises between the hits. So also with release, we tend to have that pretty fast. In fact, how we set attack and release is largely based on the sound itself. If the sound itself swells in and releases slowly, maybe a higher attack and release time is appropriate. But if the sound itself is short and punchy like this guitar a, a quick attack and release or a low attack and release is the best. I'd like you to go to your DAW now and experiment with a gate. Try to learn it in the abstract. Figure out what it does mechanically before you try to apply it in a musical context. If you already have experience using a gate, I would suggest trying to get into the finer points. Look at all the parameters you have there. Is there anything you don't understand? If there is, that's something to study, and there's always more to learn.
