You can find a version that is backwards compatible with macs running much older versions of OS X. It is a powerful recorder, editor, and converter. How about a free app for recording as well as editing sound? You can also try the free and open source Audacity sound recorder. However, audio recording was a paid feature of QuickTime Pro. Note: QuickTime 7 is also built into earlier versions of Mac OS X. This is overkill in most situations, and file compatibility is limited. The Maximum quality setting saves AIFC files using PCM S24 codec and produces rather large files.

This is good balance of quality, file size and file compatibility.

The High quality setting records M4A files with variable bitrate using the AAC code. Newer Macs have only the Microphone available as the audio source. Older Macs will generally have two input sources: Build-in Microphone and a Line-in from the 3.5mm jack.

Microphone volume is adjustable with the slider under the record button.

You may click on the Down Arrow next to the record button to select your sound input (microphone) and sound Quality settings.

You will see a very simple user interface with sound recording controls.

Open the File menu and select New Audio Recording.

Open QuickTime Player from your Applications folder.

Obs for mac 10.7.5