Digital Reverb Parameters

Digital reverb is a very complex effect. To create a natural effect, between 1000 and 3000 separate calculations are needed every second.

Using digital reverb it is very easy to produce strong early reflection patterns, something plate and spring reverbs cannot do. These reflections are very important in making the reverb sound natural.

By programming the reverb unit we can produce sounds that occur naturally, and also impossible reverberations, such as reverse or gated reverb.

Stereo Reverb

In reality, reverb comes from all directions regardless of the stereo positioning of the original sound.

Most digital reverbs use mono in, stereo out connection. This mimics the way in which natural reverb envelops the listener regardless of the direction of the original sound.
Some also use stereo in, stereo out connection. This can be used for special effects or for a dual reverb mode where the unit functions as two independent reverb units, either in mono or summing the two stereo outputs to the stereo outs of the unit.

Digital Reverb Parameters

Programming the reverb unit allows the user to precisely control the reverberation being added to a signal. In this way, we can make any type of environment to 'put' the instruments or vocalist in, from a cave to a cardboard box!

The main parameters available for programming are…

Pre-Delay Time: Sets the time between the impulse and the first early reflection. Creates an illusion of room size and helps to separate the original sound from the reverb.
Early Reflection Pattern and Level: Most reverbs give the user a choice of preset patterns (rooms, halls, plates, chambers, ambiences etc.). The greater the spacing in between the reflections the larger the room 'feels'. Some reverbs allow the user to alter the level and spacing of the early reflections.
Overall Decay Time: Sets the RT60 (the time the reverb takes to die away by 60dB after the end of the initial sound). The longer the decay time the larger and more reflective the artificial space seems.
High Frequency Damping: Simulates the absorptive properties (both air absorption and surface absorption) of a real space by making the high frequency decay time shorter than the overall decay time. Some reverbs also allow low frequency damping to simulate spaces which reflect mainly high frequency sounds.

Have a look at how these parameters relate to room acoustics and natural reverberation.
Also, here are some sample reverb settings.

This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 2.5 License.