This study investigates human brain responses to musical pitch during perception and imagery tasks using electro-encephalogram (EEG). Seven participants in the experiment were engaged in the two tasks: the first task involved passive listening to five-note melodies composed of seven pitches (C4–B4), while the second required them to imagine the same melodies guided by a flashing static note cue displayed on a piano keyboard. Using event-related potential (ERP) analysis, we explored both eye-included and eye-cleaned EEG signals. ERPs reconstructed from eye-related independent components (ICs) revealed distinct hemispheric polarity, with left-right ERP polarity reversed across listening and imagery conditions. After removing eye-related ICs, statistical comparisons between the lowest (C4) and highest (B4) pitches showed significant ERP differences across specific time windows and channels in both perception and imagery. These findings suggest a complex, context-sensitive representation of musical pitch in the human EEG, influenced by both modality and the relative height difference of notes.