Dog Park Software has released
iSpectrum Analyzer 2.0, a new version of the audio spectrum analyzer for Mac OS X. New to this release is Universal Binary support for Intel Macs. iSpectrum Analyzer costs $45 for a single user license.
iSpectrum Analyzer offers a spectrum view, oscilloscope view and waterfall frequency display, and features user-selectable bandwidths of 500Hz, 2.5 kHz, 10 kHz and 20 kHz. You can auto-center marker frequencies when setting bandwidth, select mic gain, save images to disk and more. It works with system and USB microphones.
System requirements call for Mac OS X v10.2 or later.