Using WireTap Studio, you can record the discrete audio output of any application, as well as all system audio, or record audio input from any microphone, line-in, or audio input hardware. If you can hear it, WireTap Studio can record it. Once you have recorded your audio, you can easily organize your recordings in the convenient Recording Library, and edit them with WireTap Studio's integrated lossless audio editor. WireTap Studio also boasts full Audio Unit effects support, for adding professional quality effects to your audio.
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I don't often have to capture audio but when I do, this is where I go. Select any source (an open app, an internal/external mic) and click record. Export to using any compression tech and at any bitrate. It stores the master lossless file so you can always save it out in another format without degradation. Another great Ambrosia app.
An amazing piece of kit, its so versatile and a necessity to anyone working with audio/film.