Resonance effects are known to affect vibrational spectra and electrochemical properties of substituted quinones. On the basis of the results of density functional calculations performed on several singly substituted 1,4-benzoquinones, we propose an extended resonance model which can account for the most prominent substituent effects onto the force constants of carbon-carbon and carbon-oxygen bonds. The calculations show that the two proposed resonance mechanisms are closely coupled. This interplay of the two effects renders a quantitative prediction of force constants of substituted 1,4-benzoquinone difficult. We nevertheless can give some simple rules which in many cases can give a good estimate for expected force constant changes upon substitution of 1,4-benzoquinone.