1. Musical range of an instrument. Description or number of notes from the lowest playing bass note to the highest playing treble note. (This may differ from the actual number of piano notes; for instance, a 65-note piano roll uses only 65 notes of an 88-note piano). 2. The number of playing notes plus the number of holes necessary to perform register changes and other functions. Thus an instrument may be described, for example, as having a 30-note* Synonym: key (also listed in this Glossary, definition 4). 3. Layout or diagram of the function of each hole in a tracker bar, key in a key frame, etc. 4. Dimensions of a pipe relative to its length. A smaller scale pipe has a smaller cross section for a given note than a larger scale pipe has. For example, the violin pipes in a Wurlitzer orchestrion are of smaller scale than the stopped flutes. Generally, smaller scale contributes to more prominent upper harmonics and consequently brighter tone.