Rate and Pitch
Occasionally a piece of audio needs to be played faster or slower. I’ve seen people use QLab to play backing tracks in their band. This is a quick an easy way to lower the BPMs or Beats Per Minute. I like to use the rate feature to make funny sounds that make my kids laugh. Both are good and valid uses of technology.
Whatever your reason, the Rate property can be found in the Time & Loops tab of the Inspector. By default, the Rate of an audio cue is 1. Think about this in terms of math, multiplication, anything times 1 is … the same. No change. A lower rate slows down. A higher rate speeds up.
To make the audio go slower, go down, less than one. So here’s .5, half. Here’s .95, slightly slower.
To make it go faster, choose a number greater than one. Here’s 5, much faster. Here’s 1.2, slightly faster.
You’ll notice that the audio quality breaks down the more overt the rate change.
Pitch naturally changes when you adjust rate. Slower is lower. Faster is higher. Click here to preserve the pitch. This is ideal for a situation like the backing tracks for the band. I need the BPMs to speed up but please stay in the same key!
Assignment
Try taking a song and making it go half or double the rate.
Were You Listening?
How do you keep the audio pitch the same when changing the rate at which it plays?
Answer
Click preserve pitch under the Time & Loops tab.