In tonal music, patterns of tension and resolution form one of the core principles evoking emotions. The experience of musical tension and resolution depends on various features of the music (e.g., dynamics, agogics, melody, and harmony); however, the relative contribution of different features to the experience of tension is less clear. To investigate the influence of different features on subjectively experienced musical tension, we compared continuous ratings of felt musical tension for original and modified versions of two piano pieces by Mendelssohn and Mozart. Modifications included versions without dynamics and without agogics as well as versions in which the music was reduced to its melodic, harmonic, or outer voice components. Additionally, we compared tension ratings with a loudness model. Tension ratings for versions without dynamics, versions without agogics and without dynamics, and outer voice reductions correlated highly with ratings for the original versions for both pieces. Tension rating correlations between melodic or harmonic reductions and original versions, as well as loudness and original ratings, differed between pieces and appeared to depend on the relative importance of the feature in the respective piece. In addition, qualitative analyses suggested that felt tension and resolution depend on phrase structure, local harmonic implications, and global syntactic structures of the pieces. Altogether, results indicate that discarding expressive features such as dynamics and agogics largely preserves tension-resolution patterns of the music, whereas the contributions of harmonic and melodic structure depend on the way in which they are employed in the composition.