The goal of this research is to determine whether such properties as tonality, mode, meter and tune title remain similar between different versions of the same melody. A variability in some features makes classifying and searching tasks more difficult. The author uses a corpus of traditional dance melodies on audio recordings from Macedonia (Greece), as a base for analysis. We show that, in general, none of the features – meter, mode, key and tune title – are invariable on their own, for all versions of a selected tune. At the same time, using linguistic features where the musical ones fail, and vice versa, helps to improve the chances of a correct attribution and an efficient search.It is possible now to use the examples of invariance violations to assess possible search systems for a corpus of musical works.