The Basics: Reverb

Reverb

Reverb is one of those essential mysteries the beginning producer often finds themselves struggling with. No reverb, and it is very obvious that your track is missing something (unless you're out here recording in roman-catholic cathedrals) On the other hand, I often encounter beginning producers where it seems like the moment they pull up a reverb plugin, the entire track is transported to the bat cave, and the track loses all definition and clarity. 

So where is the middle ground? Too little, and the track sounds empty, too much, and we're overwhelmed with the wash. So with reverb being one of those things that can easily be overdone, how do we know when to stop? What is the "right" reverb for all of our songs?

The Answer: There isn't one. Reverb is nothing but a tool, one we can use to create a desired effect. Reverb puts us in the space that we are experiencing the song in.

Maybe then the correct question to ask is "What is the desired mood of my song?" If you were to create a totally over exaggerated space in which you could immerse the listener in, what would it be? Is it a rock venue? A concert hall? A cave? Once we have a conception of what our space is, then we can start tackling the problem of how to create that space.

Since I can't tell you how to make a reverb specific to your song, I'm going to do something that I wish someone had done for me when I first found myself agonizing over minute reverb fixes: Describe all of the essential parameters of a reverb, and how they affect your sound.

Predelay: Predelay emulates the timing of the first initial reflections we would hear from our sound as it bounces off of a surface and comes back to our ears. Sound travels at roughly 340 meters per second (1,126 ft / s) which calculates to roughly a foot per millisecond (1.126 technically)
          Reflections are important in helping define the size of the space we are in, so if we wanted it to sound like the nearest reflective surface was 100 ft away, we would set our pre delay for 100-ish ms.

Decay Time: Decay Time is the amount of time it takes for the subsequent reflections to decay to silence. This is the main parameter for determining how long our reverb will remain after a signal passes through it.

Dry/Wet: A Dry / Wet knob controls what percentage of the signal is processed through the reverb.
          If we are processing a signal through a reverb bus, we should have this nob at 100%.

Waves "Rverb"
*note - not all parameters listed are pictured.

           

Density: Density determines the space between subsequent reflections. higher densities work well for sounds that you're hoping to thicken with your reverb. Although most often used as an exaggerated effect, you can functionally think of thickness as a result of the size of the space you're creating. The larger the space, the more reflections, and the thicker the reverb should be. 

Reflect: Reflect determines the volume of initial reflections

Diffuse: Diffuse determines the volume or prominence of our diffusion, separate from decay time.

Size: Size determines the size of the room, every reverb plugin runs different algorithms here, so use your ears to find the right size!

Input / Damping: In addition to all the controls mentioned above most reverbs will have two Eq's built into them. The Input Eq controls what frequencies are even processed by the reverb.
Damping (or sometime referred to as a diffusion network) controls the equalization of the processed signal.

Algorithmic vs Convolution Reverb

When it comes to choosing a reverb VST, you might encounter the words Convolution, or Algorithmic Reverb. These phrases refer to the way in which the computer simulates its reverb.

Convolution Reverb:  Convolution Reverbs are rad, programmers create convolution reverbs by analyzing audio signals in real-world environments. You will find that often times, convolution reverb presets are intended to emulate famous concert halls, studios, or specific environments like factories, pipes, living rooms, and concert halls

Algorithmic Reverb: Algorithmic Reverbs are the other 85% percent of reverbs that you will encounter. These are your stock reverbs on your DAW, and many other 3rd part reverbs,. through very clever manipulations of delay, phase, and gain, algorithmic reverbs do their best to artificially create a space to your specification. As a result, algorithmic reverbs are much more high maintenance in order to achieve a believable effect.  With proper tweaking, algorithmic reverbs will be able to handle a majority of your production needs.