In large audio collections, it is common to store audio content using perceptual encoding. However, encoding
parameters may vary from collection to collection or even within a collection - using different bit rates, sample
rates, codecs, etc. We evaluate the effect of various lossy audio encodings on the application of audio spectrum
projection features to the automatic genre classification tasks. We show that decreases in mean classification
accuracy, while small, are statistically significant for bit-rates of 96kbps or lower. Also, a heterogeneous