Audio effects are things which are added to sound with the purpose of warping the sound in some way, and up until this point, I haven’t talked about them very much. This is partially due to the fact that I don’t generally use a lot of audio effects in my recordings, but it’s also because I’m just not very good at using most audio effects properly. However, there’s one category of effects that is vital for a composer to try and understand; the echo.
There are two types of echoes; reverb and delay. Reverb is sort of a muddy echo… it’s most noticed when a loud sound trails off in places like cathedrals, gymnasiums or bathroom stalls 1. If you’re sitting anywhere besides an insulated sound booth, you can probably experience some level of reverb right now, although it might be too quiet to be very noticeable. Delay, on the other hand, is when a sound is exactly repeated multiple times at a lesser volume each time. Making a short yell into a canyon would let you experience delay.
In real life, reverb and delay are the same thing – sound waves bouncing at various distances before reaching your ears – but when composing music, they’re simulated differently. Here are some audio examples of reverb and delay:
Reverb and delay generally have different purposes for a musician. When using reverb, it’s all about presence. It establishes space and location in a way that no other audio effect can match. Are you in a cave? Are you underwater? Are you in the second floor of a house where thumping bass music is being played on the first floor? Reverb captures that.
Delay can also establish space when used properly on a whole song, but when used on individual instruments, it becomes a space-filling effect. The electric guitar is probably the most common instrument to use delay… it can be found in everything from U2 to Hillsong United.
That’s reverb and delay… but this post about echoes wouldn’t quite be complete if I didn’t mention a frequently forgotten and otherworldly audio effect; the reverse echo. Here’s a harp melody with reverse echo:
Hear how the sound fades in before the harp strings are plucked? That’s the reverse echo. Creepy? A little bit.2 Here’s how it’s done:
- Take the audio file and reverse it in your audio editing program. Go ahead and listen to it, because audio always sounds weird when reversed.
- Add reverb to your reversed audio file, and bounce3 it to a new piece of audio.
- Reverse that new piece of audio. There will now be a reversed echo effect on your original audio clip.
This is a great technique for giving an alien feel to any kind of audio, including people’s voices. Try it!
- What? I can’t possibly be the only person who’s yelled in a bathroom just to hear the echo, right? Right? ↩
- Why is this so creepy? Because no natural sound on earth does this. All sounds start emanate from a source as waves, trailing off in the distance. These sounds go in the opposite direction, creating a very unnatural effect. ↩
- You might be unfamiliar with the term “bounce” when it comes to audio. Bouncing is when you export any sound (MIDI or audio) to a new audio clip on a new track in your composing program. ↩