- How do you use reverb?
- What are the different types of reverb?
- Here’s everything you need to know and more!
For many of us, reverb is a treasured effect that never really gets old. Reverb plugins and hardware have an important place in music production, and it’s not uncommon to see several different reverb devices in a single mix.
Reverb has a transformative quality that can breathe life into the driest and simplest sounds. Sometimes this is done in the most subtle way, where the effect is only noticeable when it is removed.
Very often, reverb becomes a part of the instrument, adding long tails to otherwise short sounds and completely changing the character of lead lines, vocal tracks, anything!
It’s easy to take reverb for granted and take a set-and-forget approach with the presets that you know work best. This is understandable, as there are a lot of factors involved in getting reverb to sound just right, and presets are designed to save you time anyway. I’m a big advocate of using presets!
But if you want to dig deeper, you’re in the right place. We’re going to look at what makes reverb reverb, and what you need to know when working with reverb in your productions.
What Is Reverb
This may seem obvious, but it’s always worth considering the fundamentals before approaching a topic in depth.
Reverb is short for reverberation, a sound phenomenon we’re all familiar with in one way or another. We tend to think of reverberation as acoustic reflections that are only present in larger spaces, but this isn’t true – reverberation is everywhere. The ubiquity of reverb might explain why we react to it so strongly when it is used in music.
Reverb is a “natural” effect that is similar to lighting in photography and film, adding an unmistakable sense of realism when done right.
Like all effects though it can be exaggerated for artistic purposes. It’s not uncommon to hear “larger than life” reverb effects on lead lines, vocals, and powerful impacts.
How Does Reverb Work?
Because reverb is such a diverse effect, no two plugins or hardware devices are really quite alike. There are many different approaches developers can take here, and even devices in the same category can sound very different.
So there’s no easy answer to this question – but that’s a good thing!
If we want to get an idea of how reverb works on a technical level, it’s best to understand how it works within each approach.
Analog vs Digital vs Convolution Reverb: What’s The Difference?
“Digital” Reverb
This is the most common type, and I’ve put digital in quotes because there are other digital approaches that work differently to this type (like convolution reverb).
“Digital” reverb essentially involves simulating a number of individual echoes with an array of diffused delay lines. On their own, each delay sounds like a simple (but blurry) slap-back delay effect. But when added together, they create the impression of a real space.
Very often, digital reverb devices will include different “algorithms” such as plate, hall, and room. This will change a few things under the hood, often reconfiguring how the delay lines are arranged and set.
Filters are important components in digital reverb as they help shape the frequency response of a space by attenuating (and maybe boosting) frequencies for each echo. It’s common to see a “damp” control that will reduce the high-frequency content of each echo – simulating the dampening effect that softer materials have on sound.
Overall, it’s surprising how realistic digital reverb can be. It seems paradoxical as we do not usually associate “digital” with realism.
Analog Reverb
Analog reverb itself consists of a number of approaches, just like digital reverb. Broadly speaking, any reverberation that isn’t digital can be considered analog reverb. This includes electromagnetic plate and spring reverb devices, and I’m even going to include echo chambers here. We could spend time going into the subcategories of analog reverb but the truth is analog reverb is a niche topic that is relatively inaccessible for most.
99% of the time when producers are dealing with reverb, they are using plugins inside their DAW. It’s much easier to approach reverb this way than having to deal with routing audio in and out of the computer, and even then, most hardware reverb devices are still digital.
This isn’t to say that analog reverb devices are of little use – far from it. They have played an important role in musical history, and plate reverb in particular is well-liked for its dense, dreamy sound. But an actual plate reverb device will cost you a lot of money and take up a huge amount of space, so you would need to be really passionate to invest in one.
If you want to engage with analog reverb on a budget, there’s some good news: every space in real life is an analog reverb device! You’ll still need speakers and a recorder, but there’s a good chance you already have those anyway.
You can even get great results re-amping sounds through a Bluetooth speaker in an empty space, but I would recommend having a stereo recorder for the best results. In my opinion, recording reverberations in mono is a waste as you miss out on the all-important stereo image that tells us so much about the space.
Now, if you like the idea of using reverb from “real” spaces, the next type of reverb will likely be of particular interest to you…
Convolution Reverb
Convolution reverb is a special type of digital reverb that is becoming increasingly common.
With convolution reverb, we are able to “sample” real spaces using a mathematical process that is relatively easy to grasp but complex to compute (which means it uses a lot of CPU!). This means we can record an impulse in a real space, giving us an impulse response. Then our convolution reverb device will take this recording and apply these sonic characteristics to any incoming audio.
This is an objectively cool and nice effect that can go way beyond just simulating spaces – we can effectively load any sound into a convolution reverb device and get some very unique results. It’s easy to hear how convolution is used all the time as an experimental effect in film and video game sound design.
Because this is an article about reverb, we’ll leave the experimental sound design stuff alone for now and just focus on impulse responses and their relationship to convolution reverb.
After a great reverb plugin? Check out our review of Baby Audio’s Crystalline.
Impulse Responses
These are special recordings that are designed specifically with convolution in mind. They are effectively “samples” of real spaces or bits of gear and contain all the information we need to know how different frequencies respond in a space over time.
Impulse responses on their own sound like bursts of noise and aren’t really interesting until they are loaded into your reverb device.
You can make your own impulses with a clap or balloon burst in a real space and get pretty decent results. There’s an even more accurate way of doing this with tone sweeps, but it’s not always easy to get all the equipment necessary to do it this way.
In my own experience, I’ve found that popping a balloon works perfectly fine, just be aware that any frequencies that stick out in the initial sound will be present in the impulse response. This means you will want to compensate with EQ later on to adjust for the tonal quality of the noise burst, for example, balloons tend to be heavier in the lower mids.
When recording impulses, try a few different mic positions. Remember that reverberation will be perceived differently depending on where you are in a space! You’ll regret it if you are given the opportunity to record in a space but only get one little snapshot of its overall character.
Convolution devices often come with a wide library of impulses for you to choose from, and you may even find impulse responses from guitar amps and cabinets.
Your reverb device can further edit the impulse to change the characteristics of a space, but ultimately you won’t get as much control as you will with traditional digital reverb.
Common Reverb Parameters
If you’re wondering how to use reverb, the best thing you can do is understand what the controls are for. Whether you’re putting reverb on vocals, drums, or you just want to use reverb as a sound design tool, you’re going to be dealing with the same settings in different ways.
As we have learned, not all reverbs are created equal! That being said, there are some common terms that pop up time and time and again when working with reverb. Pretty much all of these parameters will be found on a traditional digital reverb device, but some may not appear on analog or convolution reverb devices.
Room Size
This is self-explanatory in terms of how the reverberation is perceived. Generally, this increases the time it takes for each reflection to be heard. Think about how sound behaves in a real room – small rooms reflect sound quickly, and the sound dies out after a short period. Larger rooms have a more “sluggish” response, and the reverberation takes longer to settle.
Decay Time
The “length” of the reverb tail, or how long it takes for the reverb to die out. This also affects the perceived size and emptiness of the space. Next to the overall wet / dry mix, getting the decay time right is crucial for realistic reverberation effects.
Just like with many other effects, it’s easy to go too far with the decay time. Just because the reverb sounds good on its own doesn’t mean it’s appropriate for the entire mix – maybe the long reverb tail is now drowning out the cymbals. Often with decay time, less is more. Try and make the reverb sound big with the size and mix controls before you reach for the decay time.
Type / Algorithm
Quite often you will see a control or menu that lets you change between different reverb models, like hall, chamber, plate, and spring. This changes the configuration of the reverberation network so that it models a particular room or device.
All you really need to know is that this will change the perceived “shape” and character of the space. Exactly how this is done is part of the dark art of reverb design, and each manufacturer will have their own unique approaches and secrets here.
Mix
The level of the reverb compared to the dry signal. Sometimes this is a simple dry / wet control and other times you are given separate faders for each. If you’re using reverb on a return channel, you’ll want to set this to 100% wet.
Once again, don’t overdo it here – it’s a common mistake for inexperienced producers to lean too heavily towards the wet signal.
Just for the sake of an experiment, try setting the mix to just 10-15% and A/B compare to the original audio. You may be surprised that even just a subtle amount can really change the sense of space. Keep this in mind next time you use reverb.
Pre-Delay
The amount of time before the reverb kicks in. This is basically just a simple delay effect on the reverb tail (or the input before it hits the effect).
If you’re trying to find the best reverb settings for drums, consider adjusting the pre-delay so that the transients are heard just before the reverb tail.
It’s often useful to slightly separate the reverb tail from the dry sound for clarity, and this can be exaggerated for a cool effect. For example, try syncing the pre-delay time to your DAW’s tempo and you can create some fun rhythmic “call and response” effects.
Diffusion / Density
Diffusion is closely tied to room density, and you may even see it called this instead. Less density / diffusion creates an emptier sound with more distinct reflections. More diffusion creates a “blurry” sound, giving the impression of a furnished or “dense” space as opposed to an empty room.
I really like less density when it comes to reverb for vocals. It helps with clarity, as diffusion can make things sound mushy. We are trained to react to the human voice, so my intuition is to preserve the quality of a voice in the reverberation.
On the other hand, I prefer higher density with drums for a glossier sound. Of course it always comes down to what works best for the track.
Damp
Damp smooths out the high frequencies in the reflections to further shape the reverb tail. This is usually done with low-pass filters. A high damp setting means more high frequencies are cut.
This simulates the way sound is dampened by different materials. For example, a room with hard walls will reflect high-frequency content that would otherwise be absorbed by softer materials.
Early Reflections
We can tell a lot about a space from the early reflections. These are the first reflections you hear, and will naturally be clearer than the later ones.
This control is usually a volume slider that is separate from the overall wet / dry mix. You may not even see this control. Depending on what reverb plugin you are using, this parameter may be “under the hood”.
The character of the early reflections will depend on the room type. If you want a reverb sound that is spacious yet doesn’t linger too long, you can boost the early reflections and cut the reverb body.
EQ / Tone
This lets you shape the tone color of the reflections. There are usually shelf filters for the low and high frequencies, and it’s not uncommon to see low and high-pass filters here as well.
Reverb tends to introduce sub-harmonics and other low-frequency noise, so it’s a good idea to cut this with an EQ. Particularly if the part is played higher up on the keyboard, reverb is notorious for creating a buildup of unwanted frequencies.
Summary
One of the key things to take away here is that no two reverb devices will sound the same, so it’s difficult to explain exactly how to use reverb when it’s such a fundamentally varied effect.
But the aim with each device is still more or less the same – to simulate acoustic reflections and add space and depth to sounds.
My advice is that you get to know how your favorite reverb devices work inside and out. As usual, you will learn a lot by experimenting here. Pick a few different test sounds and listen to how they respond to different settings. Find some presets you like, and know when to use them on the right sounds.
But with a healthy knowledge of the common controls and a familiarity with the different approaches taken to reverb, you’ll soon find yourself conjuring up amazing spaces with ease.
If you’re after some great free reverb plugins that can compete with premium software, check out our roundup of the 6 Best Free Reverb VST Plugins.