From Channel D Corporation:
Professional quality FFT vector signal analyzer, 1/3 octave RTA, oscilloscope, sonogram/spectrogram display. Includes versatile, intuitive signal generator software and more. Uses CoreAudio compatible input and output devices. Real-time analysis; Offline analysis: AIFF or Sound Designer II files (any sample rate, number of bits per sample or number of channels). The download, absent an activation code, installs a hands-on, fully-functional (and time-limited) demo that can be customized with options that mirror those available in custom package configurations. Includes hyperlinked documentation, with tutorial content.