A discrimination paradigm was used to detect the influence of phonetic context on speech (experiment 1a) and nonspeech (experiment 1b) stimuli. Results of experiment 1a were consistent with the previously observed phonetic context effect of liquid consonants (/I/ and /r/) on subsequent stop consonant (/g/ and /d/) perception. Experiment lb demonstrated a context effect of liquid consonants on subsequent nonspeech sounds that were spectrally similar to the stop consonants. The results are consistent with findings that implicate spectral contrast in phonetic context effects. (C) 2003 Acoustical Society of America.