Spectrogram version 16 is a freeware dual channel audio spectrum analyzer for Windows 2000/XP/Vista which can provide either a scrolling time-frequency display or a spectrum analyzer scope display in real time for any sound source connected to your sound card.
Spectrogram allows unlimited recording and playback of the sounds from the audio spectrum display and can provide very high resolution spectrum analysis of wave files with a wide choice of frequency bands and frequency resolution and either linear or logarithmic frequency scales.
Spectrum data logging capability is also provided. Spectrogram is ideal for any purpose related to sound spectrum analysis.
Find more about this application here.