Music apparatus for determining tonality from chord progression for improved accompaniment
US5302777A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 26, 1992 |
| Grant date | Apr 12, 1994 |
| Priority date | — |
| Expiry date | Jun 26, 2012 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S84/22
- WIPO fieldOther consumer goods
- WIPO sectorOther fields
Abstract
A tonality extractor analyzes a chord progression (CP) to determine an available pitch class set (PCS) at each chord time of CP using stored musical knowledge base. The available PCS is determined differently depending on musical situations. A resultant PCS succession is most accurate and assures a natural stream of musical tonality free of a spurious modulation. An automatic accompaniment apparatus utilizes the tonality extractor for desired accompaniment performance. A modulation compensator avoids generation of a pitch range shift in the accompaniment line at the time of modulation (change of key). A style-grouped pitch change table in combination with a style-grouped reference accompaniment pattern memory optimizes accompaniment pitch contents to respective musical styles while requiring only a small storage space. An accompaniment pitch forming device using stored accompaniment note index data and a pitch table linked to the note index and tonality data controls accompaniment pitch line so as to vary in a pleasing way depending on tonalities.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.