Getting a Leslie Speaker Effect in Adobe Audition

Adobe Audition's vast array of effects--combined with its relatively small asking price--is one of the best reasons to get the software. If you're recording music at home, you need something as powerful and versatile as Audition.

One of the cooler and more accurate effects that the program offers is a virtual Leslie speaker effect. Leslie speakers were speakers that achieved a tremolo-like sound by actually spinning inside the amplifier or organ. I've got one in my Hammond organ, a real one, but when I record I prefer Adobe Audition's Leslie effect. It's easier to control, and there are a number of little issues that I don't have to deal with (such as the repetitive whoosh of air that a real rotating speaker will create). If you're interested in miking a Leslie speaker, I'll get to that in one of my next few articles, but for now, here's a look at recreating the sound of a Leslie through Adobe Audition.

Record your sound. This effect works best on mono sounds, but in a pinch it'll work on stereo stuff, too. Hit Alt + 2 to bring up your mixer and click one of the little arrows under effects panel to bring up Adobe Audition's list of effects.

Choose Modulation and click Sweeping Phaser. You can then roll through the presets to find three basic Leslie effects: slow, medium, and fast. If you want that old furious organ sound that you've heard on plenty of rock recordings, start out with the fast preset. If you'd prefer something slower to go with a slower tune (duh), go with medium or slow. Experiment a little bit; you'll find out how different settings work and how to take more control over the fake Leslie speaker.

Change the settings. Once you've had your fun, you can get a really professional sound by changing the rotations per beat number in the lower right hand corner. This only works if you're recording a song to a steady beat and you set the BPM in Adobe Audition before you started. The program will automatically adjust the Leslie so that the speaker rotates in time with the song (or out of time, if you'd prefer).

If you didn't use Audition's metronome to record your song, you can still do some quick math to manually figure out how many milliseconds to set the phase at. Take 60,000 (the number of milliseconds in a minute) and divide it by the BPM of the song. Keep dividing by 2 to subdivide into quarter notes, eighth notes, etc. Enter your number into the controls of the phaser to change the sound of your fake Leslie. Experiment a bit to get the sound that you want, and note that you can also use the above equation to set delay, reverb, and other time-based effects for a more natural sound in your recordings.

Have any questions about getting a Leslie speaker effect in your home recordings? Post in our comments section below.