Expressive power under context-free and linear restrictions

Characterize the classes of musical compositions that can be orchestrated by n-generative rule-synchronized music grammar systems when each component grammar is restricted to context-free rules or, more strongly, to linear rules.

Background

The current system relies on scattered context grammars in each component to capture complex interdependencies across instruments. The authors propose restricting components to simpler rule families (context-free, linear) and pose the question of what music remains generable under such constraints.

This seeks a fine-grained understanding of the expressive trade-offs between more powerful synchronized rewriting and simpler grammar components.