Since only simple symbol-based manipulations are needed,n-gram indexingis used for naturallanguageswhere syntactic or semantic analyses are often difficult. Music, whose automatic analysis for patterns such as motifs and phrases are difficult, inaccurate or computationally expensive, is thus similar to natural languages. The use of n-gram in music retrieval systems is thus a natural choice. In this paper, we study a number of issues regarding ngram indexing of musical features using simulated queries. They are: whether combinatorial explosion is a problem in n-gram indexing of musical features, the relative discriminationpower of six differentmusical features, the valueof n needed for them, and the average amount of false positives returned when n-grams are used to index music.