Use Two iPods to DJ

Got a party coming up? Leave that stack of vinyl at home and take two iPods with you to mix it up digital-music style.

It’s inevitable that when a new music format becomes popular, people will want to DJ with it. It happened with vinyl, it happened with CDs—well, okay, it didn’t quite happen with eight-tracks or cassettes. But what about digital formats such as MP3 or AAC? It is possible to DJ with your iPod, and although the iPod presents some barriers to creating a professional-sounding DJ show, you can still achieve good results. There are two main ways to DJ with your iPod: the first way consists of connecting two iPods to a mixing board, and the other is achieved when you connect two iPods to your computer.

Two iPods and a Mixing Board

To DJ using two iPods and a mixing board, you will need the following items:

  • Two iPods

  • Two headphone-jack-to-RCA cables

  • A mixing board

  • An amplifier

  • Speakers

This setup mimics the traditional basic DJ setup of two turntables connected to a mixing board. We are substituting iPods for turntables, but unfortunately, this is not just a simple matter of swapping one for another. There are a few issues we need to address first.

Connectivity and amplification.

For this setup, we will utilize the headphone jack on the iPod. This allows us to cut a computer out of the equation, providing a more portable setup. Simply connect your two iPods to your mixing board using headphone to RCA cables. There is, however, a problem with using the headphone jack: the lack of adequate amplification. Sure, the iPod offers enough power to jack up the volume on your headphones, but when you’re trying to blast the ears off your audience with speakers, it’s simply not enough. If you connect your iPod directly to your mixing board through the headphone jack, you’ll find that the sound quality degrades tremendously right around the halfway volume setting on your iPod. You will be able to increase the volume significantly from that point, but the quality of sound will be unacceptable.

You could run your iPods through your receiver for amplification first and then out to the mixing board, but this presents a problem when it comes to transporting equipment. If you plan on setting up a permanent system to DJ, this might be a viable option. But if you’re like me, you’ll find the idea of lugging around a receiver in addition to your mixing board and speakers undesirable. To fix this problem, I have run each of my iPods through the PowerWave USB Audio Interface and Desktop Amplifier, from Griffin Technology (; $99.99), and then connected the amplifiers to the mixing board. This provides a huge boost in fidelity, especially at high volume.


Mixing boards span the gamut in sophistication, quality, and price. If you are just looking to fool around with mixing two iPods together, you can get a basic mixer at RadioShack for around $75. If you are a more seasoned DJ, you probably already have a mixing board so you don’t need to upgrade your current mixing board to use iPods with it—just get hold of some headphone-jack-to-RCA cables.

Pitch control and beat matching.

One of the fundamentals of seamless mixing is the ability to beat match. Beat matching is the term given to speeding up or slowing down one song to match the beats of the next song. This technique is executed by adjusting the pitch of the audio, thus speeding up or slowing down the music. Unfortunately, the iPod currently does not allow you to do this. So how in the world can you DJ, then? Well, you won’t sound like Fatboy Slim, but you can still string together songs by using the cross-fader on your mixing board. The lack of pitch control only means that you have to carefully choose the order of your songs.

Song choice is key to a good DJ set. Without the ability to beat match, it is important to be able to choose songs that sound good together, especially at the endings and beginnings. By reducing the volume of song 1 while increasing the volume of song 2, you can create a smoother transition between tracks. I have found that songs with talking at the beginning of the song are good to transition to. This is common in hip-hop and rap songs. That way, you hear talking on song 2 over the music of song 1. In addition, you can sometimes use spoken-word or other multimedia clips, such as excerpts from TV broadcasts or movie quotes, as bookends to a song with music.


Another barrier to a professional iPod DJ show is the inability to scratch. This technique was created by DJs working with vinyl records, but with the new CDJ units, DJs have been able to mimic the effect with CDs. Unfortunately, this is not currently possible with the iPod. It’s a shame, too, because the scroll wheel would be a perfect interface for it. You will find some instances on the Internet where people have suggested creating a faux scratch effect with their iPods. Tapping the center button and gently jogging the music back a fraction of a second achieves this. However, all my tests of this technique produced an unsatisfactory sound, similar to a skipping CD. I recommend not doing it, because it might confuse the audience into thinking you ripped your music incorrectly.

The two iPod/mixing board setup is convenient to transport and simple to set up, but lackluster when it comes to overall quality of sound. It’s an inexpensive way to entertain your party guests, but if you’re looking for an authentic DJ-show sound, you’ll need to add a computer into the mix.

Two iPods and a Computer

The other option when DJ-ing with two iPods is to connect both iPods to a computer. This configuration has many advantages. First and foremost, DJs can create a more professional-quality show by using mixing programs such as Traktor DJ Studio Pro (; $229). Traktor DJ Studio Pro allows DJs to use all the techniques they normally would with turntables: they can simulate scratching, adjust pitch, loop samples, beat match, and fade. And they can do all this without dragging around milk crates full of records!

In addition, having a computer setup allow DJs to connect to the Internet or private FTP servers while performing. This enables access to a wide range of music and samples, far beyond what you can hold on your two iPods.

Here’s what you’ll need for this setup:

  • 2 iPods

  • A laptop

  • 2 FireWire ports or a FireWire hub

  • An audio-out port

  • Traktor DJ Studio (or a similar mixing program)

  • An amplifier

  • Speakers

By connecting both iPods to your computer, you can create great mixes quickly and easily. Traktor DJ Studio is fully compatible with iTunes, so all the songs in your iTunes library are accessible on the fly, as are the songs loaded on your iPods. Between two full iPods and the hard drive on your lap-top, you could have 30,000 songs at your fingertips. With that amount of material, you should be able to find enough songs to play in your set! And with Traktor DJ Studio, you can beat match, loop samples, and scratch flawlessly. This is a must for DJs who want to use digital audio files for their sets.

When you first open Traktor DJ Studio, a setup window appears. Set your preferences for importing iTunes playlists in the Browser tab, as shown in Figure 1-8.

Traktor DJ Studio’s Preferences window

Figure 1-8. Traktor DJ Studio’s Preferences window

When you’ve completed your setup, your iTunes playlists appear in the Browser window. I have named the playlist for this demonstration “New Mix,” as shown in Figure 1-9.

While a track is playing, you can “scratch” by simply clicking and dragging. To create a more “turntable” feel and scratch the track with finer resolution, hold the Shift key while clicking and dragging, as shown in Figure 1-10.

Cross-fading between two songs is easy. Simply click and drag the cross-fader slider to transition the first song to the second, as shown in Figure 1-11.

Your available iTunes playlists

Figure 1-9. Your available iTunes playlists

Scratching, digital style

Figure 1-10. Scratching, digital style

Sometimes, it is necessary to adjust the tempo of one song to match the tempo of another. This can be accomplished by using the tempo level adjuster, as shown in Figure 1-12. Drag the slider up, and the speed of the song slows down. Drag it down, and the speed increases.

Cross-fading between two tracks

Figure 1-11. Cross-fading between two tracks

Adjusting the tempo

Figure 1-12. Adjusting the tempo

Looping samples from a song is another common technique used by DJs, and Traktor DJ Studio makes it easy (see Figure 1-13). For example, clicking on the 8 button and then clicking on the SET/IN button tells the program to set a loop eight beats long from the beginning of the playhead. The loop is marked by green lines and boxes that read S and E. Click Play, and this sample loops continuously.

These features are the tip of the iceberg. Traktor DJ Studio allows the most seasoned DJs to do virtually everything they can do with conventional equipment.

Whether you are using the traditional two-iPod/mixing board setup or the two-iPod/computer setup, you can achieve great results. These setups have become invaluable to some DJs. The iPod is not just a great consumer product anymore; with its huge song capacity, small size, and excellent sound quality, the iPod is now perfect for the seasoned professional too.

Gregory Ng

Looping a sample

Figure 1-13. Looping a sample

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