It’s really a simple process that can be done very cheaply–most of the time. If you want to plug straight into your Mac instead of any kinds of external devices such as a Digidesign M-box 2 (which I use) you don’t really need a whole lot. Assuming you’ve got instrument cable for your guitar, you really only need one other part: an adapter.

Note: This article assumes you have an electric guitar, an acoustic-electric guitar, or at the very least a pickup for your acoustic guitar.

This article is specifically written towards Macs, which seem to have very nice sound cards built into them–even the MacBook line. The MacBooks and Mac Pros all have Line In ports which you can plug an 1/8″ connector into to pipe sound in.

Note: The new 13-inch MacBook Pro has a combined audio in/out port. I’m guessing this has to do with trying to cram so much into such a small laptop. In System Preferences you can switch between these functionalities and use it as a Line In port for your guitar. The downside to this is, if you’re using external speakers or headphones to monitor your recording…you simply can’t.

Getting the adapter

The main hurdle you have now is that instrument cable as used to connect guitar to an amplifier has 1/4″ connectors on the ends. You’ll need an adapter to convert that 1/4″ to 1/8″ so you can plug it into your Mac’s Line In port. You can find these wherever you normally look for electronic/audio components–RadioShack for me. The adapter looks something like this:

I got mine at RadioShack for $2.69. Not bad, huh? Note that this adapter is a mono adapter. You could get a stereo adapter if you wanted, but as most instrument cable is mono so you would have a wasted channel.

Volume

Now’s where things get a little variable. I have a Stratocaster which has Seymour Duncan pickups in it, which provide a very strong signal. With this setup, I can go to System Preferences>Sound, select Line In as my audio in port, and then go to GarageBand, Audacity, or whatever recording program I want and record perfectly fine that way. I don’t have to turn my volume knob all the way up in order to get a good signal for recording. However, depending on your guitar you may have a really low signal or a really hot one.

If your signal is fine, then you’re done! You’ve got a basic but functional way to record your guitar into your computer. From there you can amplify the signal using software amplifiers (such as Guitar Rig or the amps built into GarageBand). Or, if you have another instrument cable you can run your audio out from your “real” amplifier into your Mac but be careful about how hot your signal is coming into your Mac–too loud can damage things.

If your signal’s not fine

In the case that your signal is so low you can barely hear it, even with the guitar’s volume knob and the volume setting in System Preferences dialed all the way up, you may need to invest in a pre-amplifier to boost your signal.

In my previous article I suggested Griffin’s iMic, which will work, but if you’re going to be setting up a personal home studio-type environment you may want to splurge and get an M-box from Digidesign or something like a PreSonus Audiobox USB. These are more than pre-amps: they are audio interfaces. Consider them a seperate, dedicated sound card for your Mac. These types of things are handy for when you need to minimize your latency by “outsourcing” the processing of your guitar signal.

A note about latency

If you notice that there seems to be a delay between when you strike a note and when you hear it come through your computer you may need to get an audio interface like mentioned before in order to free up some of your system resources. Varying factors like amount of RAM, processor usage/speed (don’t be ripping DVDs with HandBrake while trying to record something), and even hard drive speed in some applications can cause your recording to lag behind. Although you can adjust this lag in your recording afterwards, it can be annoying when trying to record tracks to a drum beat and you’re always off a few milliseconds.

Overview

Hopefully, things have gone well for you. As I said, in most cases with Macs you should be fine with just the adapter. Please note that going straight through the sound card in your Mac is not the best way to do this ‘professionally’ but for simple home projects and song demos this is definitely an effective and much cheaper way to try things out without spending hundreds in pro equipment.

Feedback

Have fun jamming and please leave your comments below if you have questions and if this article has helped you in any way.

Evidently this problem doesn’t happen to everyone. In most cases the software installs and just works—not for me. I had to Google up a storm and do some thinking. My search led me to a relatively unknown feature in OS X’s handling of MIDI devices: aggregate devices. In order to pipe sound into Guitar Rig, you have to create an aggregate device.

First, I’m going to explain how it works and what it really means, then I’ll show you how to do it. You can skip this part you don’t care.

How it Works

The input comes into your aggregated device and immediately passes through and out that device’s “output”. Guitar Rig sees this “simulated” device as a real device and allows you to access it inside the program. Guitar Rig actually thinks this device is one of the Guitar Rig Kontrol hardware devices that you have plugged into your computer.

How You Do It

Although it’s not very prominent, there is an application that came with OS X for managing MIDI devices. That’s what we’ll be using here. It’s called Audio MIDI Setup and you can find it in the Utilities folder of your Applications folder—or better yet use Spotlight to find it (Cmd+Space, then type “Audio MIDI Setup” and press enter).

Once you’ve opened the program you’ll need to select “Open Aggregate Device Editor” from the Audio menu at the top of your screen. Click the plus sign (+) to create a new device and then click the check boxes next to “Built-In Input” and “Built-In Output”. Do not click the checkbox next to “Built-In Microphone”!

Click “Done” and close the program.

Now all that’s left to do is go into Guitar Rig and set your Output Device to your new device (whatever you named it). Once you’ve done that, you’ll see your device show up as an option for the “Input”.

In Conclusion

I hope this helped somebody out there out. Have fun messing with all Guitar Rig offers you—which is quite a lot! Keep on rocking. I’d love to hear any of your recordings, just comment me a link.