Video icon 64
Build your creative skills with practical video courses from Tuts+. Start your free trial today.

Using Logic Pro 9's Varispeed to Tempo-Shift Entire Projects


One of the many excellent new features of Logic Pro 9 is Varispeed. Varispeed gives you the ability to speed up and slow down your projects — not just a single instrument, but the entire project can be instantly tempo-shifted. Let’s look at how it’s done.

Republished Tutorial

Every few weeks, we revisit some of our reader's favorite posts from throughout the history of the site. This tutorial was first published in November of 2009.

Why Use Varispeed?

Varispeed isn’t the sort of tool you’ll need to use every day, but it’s the sort of tool that you like to know is available to you. Every now and then you’re halfway through a project when you decide that the tempo just isn’t right and the song should be slower or faster. Varispeed allows you to determine which tempo suits the song better, quickly and easily.

Alternatively, you may be having trouble recording a difficult part in the song. While Varispeed may not be your first port of call, after struggling with the part for too long it’s convenient to be able to slow the whole project down, record your part, and snap it back to normal speed afterwards. Your new part will be in time with everything else.

If you feel like a cheater recording the part slower, at least you can practice at a slower tempo before working your way back up.

And, for maximum fun, Varispeed can be used as an effect as well.

Step 1

Varispeed isn’t instantly available from the transport bar on a default installation of Logic Pro 9. If you right click anywhere on the transport bar you’ll get a menu option that says “Customize Transport Bar…” — click this.

This is what you’ll see:

Tick the box that says Varispeed in the second column, and then click OK.

Step 2

You should now see this button among the group of buttons on the right hand side of your transport bar:

If you click this button, Varispeed is enabled, and you’ll see a section of the transport bar’s information panel go orange.

Step 3

Your project still sounds the same at this point. Varispeed is on, but the change in speed hasn’t been specified yet.

Before we start tempo-shifting, let’s listen to the original piece. I didn’t want to record a bunch of music for this tutorial so I’ve just arranged a little tune from stock loops. It’s a bit busy because I wanted to demonstrate how well Varispeed tempo-shifts multiple audio and MIDI tracks all at the same time.

Go back to the orange panel on the information bar. If you drag the bottom section with the numbers in it up or down, you’ll change the tempo. The default view measures the change in percentage, and that change can be between -50% and +100%.

I have to say that I’m pretty impressed with how well Logic retains the tune’s cohesion at the most extreme ends of the spectrum. Here are the -50% and +100% versions, respectively:

Step 4

That’s cool, but modifying the tempo by percentages doesn’t quite give us control that’s fine tuned enough for a real song. We need to be able to modify the number of beats per minute directly.

In the top half of the orange section of the transport bar’s information area, there’s usually text such as “Speed Only”. Click and hold here to bring up a menu, and select “Resulting Tempo”. The percentage is gone, and now you can set a specific tempo, which gives you much less comedic and more useful results.

Here’s our song at 130 BPM, up from a base of 120 BPM:

Step 5

I mentioned that Varispeed could be used as an effect. Most features that allow you to speed up or slow down entire songs try to retain the original pitch of the track, which is what makes using Varispeed to record difficult parts possible.

But Logic gives you the option to change the tempo and the pitch in parallel. If you lower the tempo, you lower the pitch. If you increase the tempo, you increase the pitch.

This allows you to crank the tempo and create one of those silly chipmunk songs that I always see in American movies or create a dark, warped effect by bringing the tempo and pitch down low.

Here’s an example of each, at 66 BPM and 178 BPM respectively:

To do this, hold down on the top row of the Varispeed information section on the transport bar. This brings up the menu again. Now, switch from “Speed Only” to “Varispeed (Speed and Pitch)”.

At this point you can change the tempo or speed change percentage and laugh at the results.