XO Wave: Using Audio Hijack Pro with XO Wave (Technical Note)

If you're looking for a quick, easy and free way to route audio from one app to another, check out Soundflower from Cycling 74. Though Soundflower lacks Audio Hijack Pro's ability to "hijack" sound from any app and set up an automatic, unattended recording schedule, it does let you route sound from any app to any other app. In combination with an audio recording app, such as XO Wave, you can use it to record audio from just about any source, even streaming audio.

Note: As of 1.0.3, XO Wave is no longer compatible with Audio Hijack Pro. This change was necessary because the combination of XO Wave's multiprocess architecture and a bug in Mac OS X 10.5 ("Leopard") caused problems with the Dock. In the meantime, we recommend Soundflower (see sidebar) or WireTap Pro, although we have not tested the latter extensively.

This page describes how to use XO Wave with Audio Hijack Pro, a popular program for recording and redirecting audio on Mac OS X. Audio Hijack (non-Pro) does not to work with XO Wave, because it lacks the required "Instant Hijack" feature.

In addition, we have briefly tested WireTap Pro, a competing product, which worked without special configuration. Because all of these packages intercept the audio between XO Wave and your sound card, we cannot guarantee the performance of XO Wave with such software installed. In particular, these packages could cause audio dropouts, especially in low-latency, high-load scenarios.

Warning: the Instant Hijack feature is a "haxie", and as such requires Unsanity's Application Enhancer (also called "APE") to work. Application Enhancer provides new capabilities to Mac OS X and applications by modifying the behavior of the operating system. This gives haxies remarkable flexibility, but can also cause problems in otherwise stable applications, as they perform unsupported and unanticipated manipulations to the running operating system introducing unlimited permutations for application interactions. Please consider this carefully before installing APE (Audio Hijack Pro does this automatically when the Install button for Instant Hijack is clicked), and for troubleshooting systems with APE installed. Before reporting crashes or other trouble on systems running APE, please try to reproduce the problem without APE running, and mention APE in the problem report. Audio Hijack Pro offers an Uninstall button to remove Instant Hijack and APE. Rogue Amoeba has a web page that explains application enhancers in more detail.

Setup

Because of XO Wave's architecture, Audio Hijack Pro doesn't work correctly with XO Wave "out of the box". Instant Hijack must be installed, and Audio Hijack Pro must be configured to acquire hijack from the XO Wave audio engine. Fortunately this is fairly simple.

Set up Instant Hijack

• Download and install Audio Hijack Pro.
• Launch Audio Hijack Pro by double-clicking its icon.
• Select Audio Hijack Pro:Install Extras....
• After selecting the Instant Hijack tab, click Install.
• Log out and log back in.

Configure Audio Hijack Pro to work with XO Wave

• Launch Audio Hijack Pro.
• Control-click the XO Wave icon, and select Show Package Contents from the pop-up menu.
• Open Contents and then MacOS.
• Drag XOengine and XOengine-double into Audio Hijack Pro's Main Window, into the area labeled Component.

Using Audio Hijack Pro

You can now capture and record output from XO Wave just like any other application; the only difference is that you must tell Audio Hijack Pro to connect to XOengine or XOengine-double instead of XO Wave. From Audio Hijack Pro, just select XOengine or XOengine-double, depending on which audio engine you are using, and click Hijack. You will then be able to add effects, record, and do whatever else it is you do with Audio Hijack Pro. Note: Audio Hijack Pro will start adding noise to your output after ten minutes unless you purchase and register Audio Hijack Pro. Nothing is wrong with XO Wave, Audio Hijack Pro, or your system; you just need to pay for Audio Hijack Pro to get rid of the noise.