Hearing Backwards

Why does everything sound cool backwards? It doesn’t matter what it is, play it backwards and you have a brand new unique sound. The big change you notice when playing a sound backwards is that the envelope of the sound has changed. The transients and attacks are gone. The sound sort of swoops into itself. It’s a very exciting effect. Luckily, playing a sound backwards is also one of the easiest effects we can achieve with sound. Let’s take a look.

In The Old Days

Back in the analog tape days playing a sound backwards was very simple. All you had to do was take the tape off of the machine, turn it over and hit play. Your recording now played backwards. It was slightly more complicated on multi-track tape machines because flipping the tape over changed the track on which the sound played back. In other words, a sound that was recorded on track 1 of a 4-track machine would play back on track 4 when the tape was flipped over.

The Digital Days

Nowadays, reversing a sound couldn’t be easier. Almost every digital audio editor I can think of has a reverse feature. All you do is select the portion of audio you would like to play backwards and then select the reverse function. That’s it!

Now Try This

If you have never tried applying time-based effects to a sound before you reverse it I would highly recommend you do so right now.

  1. Select a sound to use for this example
  2. Apply a heavy reverb with lots of decay to the effect. When I say apply what I mean is process the reverb onto the sound so that you have a new audio file to work with. Depending on your software this is often called “bouncing to disk” or “processing” the effect.
  3. Take your new “reverb-heavy” sound and reverse it. What you should hear is a sound that builds slowly as the reverb tail flows directly into the actual reversed sound.
  4. Try this same trick with a stereo multi-tap delay instead of reverb. I promise you’ll love the results!

For more fun, try this variation of the above technique.

  1. Select a sound to use for this example
  2. Reverse the sound
  3. Apply a reverb or delay to this reversed sound
  4. Reverse your sound again. What you should hear is the reversed reverb or delay preceding or swooping into the original non-reversed sound. I use this effect all the time!

That should be enough for you to work with for now. Try these techniques out on your own sounds. As always, tell me what you think. Are these articles helpful? Have I left anything out? Leave me a comment and let me know.

Do you Pitch Shift? If not, maybe you should.

One of the first things I do when I sit down to create some new sounds is grab a few I want to work with and start pitch shifting them. For some reason sounds almost always take on a completely different and exciting vibe when you push them out of their normal pitch range. I would suggest that you try this on any of your newly recorded sounds. You are almost guaranteed to have loads of fun, as well as many new additions to your sound library. Here are the basics of pitch shifting sound.

Down Shift, Up Shift

Pitch-Shifting a sound down several octaves will often yield an eerie soundscape or drone. This works especially well with sounds that have sharp transients and a long decay, like cymbals and bells.

Pitch-Shifting a sound up a few octaves tends to give it a very sharp glassy sound. In some instances you will also begin to notice some rhythmic content in the sound that wasn’t obvious in the original. This happens a lot with speech. We talk in rhythmic patterns that aren’t really obvious until you speed things up by a couple of octaves.

The Mechanics of Pitch-Shifting

In the old days, the only way to change the pitch of a recording was to play the tape back at different speeds. Playing a tape back at half speed would cause the recording to sound an octave lower and double it’s original length. Analog tape machines, whether reel-to-reel or cassette, usually included some control that changed the tape playback speed. Most reel-to-reel machines allowed playback at speeds ranging from 7.5 inches per second (ips) to 30 ips. Cassette machines would often feature a pitch control knob that would alter the playback speed to certain degrees. The whole point is, record a sound at a fast tape speed and play it back at a slow tape speed. Instant Halloween sound effect!

Pitching-Shifting in the digital world is simple. Most digital audio software offer a pitch control that allows you to input how much up or down you would like to shift the original sound. One of the cool things about living in the digital world is that we are able to change pitch without changing the length of the sound, something that was impossible in the analog world.

One Thing Doesn’t Sound Like The Other

I would encourage you to try pitch-shifting your sounds in as many different ways as possible. If you have one, use a tape deck. Then turn around and pitch-shift that same sound in Pro Tools. You may notice a difference. Also, don’t assume that all digital audio software sounds the same. I’ve performed the same pitch shift effect on the same sound in Audacity and Digital Performer and they both sounded drastically different. Use this to your advantage when you are creating new sounds for your music.

What About You?

How many of you use pitch shifting on a regular basis? Is it something you never think about or is it a cornerstone of your sound design arsenal? Leave a comment and let me know. I’d love to hear from you.