We investigate several measures of voice quality (VQ) to improve tone recognition in Mandarin Chinese. We find that band energy measures such as Spectral Balance (Sluijter and van Heuven, 1996) work better than measures based on glottal flow estimation and harmonic-formant differences. We also determine a set of bands and measures that improve tone classification accuracy on broadcast news speech to 64.1% from 60.4% when added to a traditional pitch-duration-intensity set of features. Most improvement is for the neutral tone, for which the F score increases from 0.345 to 0.619.