Various stationary and nonstationary spectral analysis methods are utilized to analyze two-channel data obtained from the ear of an anesthetized guinea pig. One channel was recorded from a microphone placed in front of the ear, while the second was simultaneously taken from an electrode on the round window of the cochlea. A stationary white Gaussian acoustic source was used to obtain an estimate to the transfer function of the ear. This was accomplished through digital computer calculations of the auto and crosspower spectral density functions, along with the coherency function. Linear phase changes and resonances were observed in the frequency regions exhibiting high coherency. A spoken sentence was utilized as a nonstationary source. The balance between frequency resolution and time definition is illustrated on various displays of time-varying spectra. They include two-dimensional, three-dimensional, and ordinary spectrogram types of displays.