If you've never hosted or attended a GoToMeeting meeting, you're missing out! It's a great service that allows you to host or join a meeting using VoIP (voice) and video-sharing to or from anywhere in the world! As long as your Internet connection isn't too slow, both audio and video quality is superb.
One complaint that I have with the service, however, is that the audio input options are very limited. So limited, in fact, that it's really only designed to pick up your voice as you speak using the built-in microphone. In most cases, this works fine, but in some cases, it would be great to play audio from iTunes (for example) and use that as the source of audio. While GoToMeeting doesn't offer a way to do that natively with their software, there is a 3rd-party solution that helps solve this issue.
Sound Siphon (by Static Z Software) satisfies that need by creating a virtual audio input. When GoToMeeting gives you a list of audio inputs to choose from, it builds that list from the list of physical audio inputs offered in OS X. In most cases, the built-in microphone is the only option. By creating a virtual audio input, Sound Siphon tricks OS X into thinking that it has another physical audio input to choose from.
In order to use Sound Siphon, you must first download the app. After the app has been installed, we'll start by creating a new virtual audio input. To do this, we click the [+] in the lower left-hand corner.
We want to name this new virtual audio input something meaningful, so we'll call it "iTunes Audio" (since we will be using this virtual audio input to capture and stream audio from iTunes). Once the audio driver has been created, we need to choose the app that it will capture. Again, since we want to capture audio from iTunes, we will choose iTunes as the audio source.
By the time we're done, our new virtual audio input settings should look like this:
Now we're ready to use it. To activate Sound Siphon, we click on the "On" button in the top left-hand corner.
This enables the audio capture and makes it available for other apps to use. In this case, we will now open a GoToMeeting session. Once the meeting has started, we can switch the audio input from "Built-in Microphone" to "iTunes Audio" (the virtual audio input that we just created in Sound Siphon).
From this point on, the audio that will be streamed to the meeting participants will be the audio played from iTunes. If you want to switch back to the built-in microphone, simply switch the input source back to "Built-in Microphone", and you are free to speak again.
If you want a little more creativity, you can also use this to play welcome music or even audio "commercials" for your participants while you wait for all parties to join.
Another great use for this is capturing audio from various sources to record in audio editing apps like GarageBand. If you can play it, Sound Siphon can capture it and allow you to use it in just about any way you can think of.