Types of Audio Effects
In this guide, we’ll take a look at the various audio effects used in live and recorded settings. These effects are typically used to enhance the overall sound of an instrument, track, or song. Let’s take a look at the types of audio effects and their uses.
Time-based effects include delay, reverb, chorus, phasing, and flanger. All time-based effects have differing properties, but what they all have in common is they take an input sound, delay it or alter the timing, and play it back for a pre-determined amount of time. This allows the musician to create space and depth within their music.
Delay is a time-based effect that holds an input signal, delays it, and then repeatedly plays it back for a certain amount of time. This creates a ‘repeat’ effect which typically decays in volume over time. What sets delay apart from the other time-based effects is it’s easy to distinguish these repeats as individual echoes as opposed to being squished together.
Reverb differs from delay in that instead of creating distinguishable echoes, it blends the echoes together. As a result, sounds begin to emulate specific environments – with more reverb resembling larger spaces, and less reverb resembling smaller spaces. This can come in handy for recording when you want to mimic a setting, but are not able to actually record there. Popular reverb choices are ‘hall’, ‘church’, and ‘room’.
Chorus is used as a very fast delay that slightly changes the pitch of the delayed sound. This creates a fuller sound, and is often used on vocals.
Phasing splits a signal into two copies of itself, shift-phases one, and then puts the two copies back together. This creates peaks and notches, or a ‘wave’ sound from an oscillating frequency response. This effect can take a simple note and turn it into a symphony, which was often used on keyboard in classical rock.
Flanger is a type of phasing, but where they differ is flanger takes that second copy and mixes in notes that are harmonically related within the peaks and notches. This creates the popular flanger ‘whooshing’ sound and is usually used on a guitar. Popular musicians that have used flanger include Eddie Van Halen, Heart, and Jimmy Hendrix.
Octave effects work by mixing an input signal, such as a guitar note, and a synthetic note that is either an octave lower or higher than the original signal. This creates a significant amount of depth for just a single instrument. For example, a guitarist playing along with a lower octave can create the illusion that a bass is playing as well. On the other hand, a guitarist playing with the higher octave can create that signature “screaming” solo sound.
Distortion is arguably one of the most popular effects used in the music world today. It achieves its signature ‘crunch’, and ‘fuzz’ sound by clipping the signal with added harmonics.
Compression is a simple concept, but is a very helpful tool in the studio. This effect lowers the loudest levels on a track, and boosts the quietest parts, allowing for a more even volume range across a track or song. This prevents loud sections of a track from becoming overwhelming, or quiet parts from being drowned out within the mix.
Equalization is used to adjust the levels of frequencies for a specific track. This is often accomplished by boosting or lowering high, mid or low frequencies to a desirable level.
Equalization, or EQ, can help with any deficiencies that may come from your physical space or instrument.
For a more in-depth read on the practical application of effects we recommend checking out Columbia University’s write up on mixing, EQ, compression, reverb, and more.