Patent US4987600A successfully refreshed from Google Patents.
US4987600A
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Digital sampling instrument
Assignee: Creative Technology Ltd
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Filing: 1989-08-03
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Granted: 1991-01-22
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Expires: 2009-08-03
Abstract
Abstract A digital sampling instrument is disclosed. The instrument provides the capability of accessing and outputting stored digital data within a single clock cycle. The instrument also provides improved volume scaling for sound generation and further eliminates redundant loading of a particular sound into a sound memory.
Inventors
- 👤 David P. Rossum
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 22:30
CPC Classifications
G; G10; G10H; G10H1/00; G10H1/0033; G10H1/0041; G10H7/00; G10H7/002; G10H2250/00; G10H2250/131; G10H2250/161; G10H2250/541; G10H2250/645
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
136 words
A digital sampling keyboard instrument for encoding digital data samples having a certain number of bits representative of a particular musical sound having a first fidelity comprising: means for creating differences between successive ones of said digital data samples, means for creating the logarithm of said differences to form compressed logarithmic differential data which is compressed to a fewer number of bits than said certain number of bits, means for storing said compressed logarithmic differential data, means for adding time varying logarithmic encoded volume coefficients to said stored compressed logarithmic differential data to form added compressed logarithmic differential data, means for creating the anti-logarithm of said added compressed logarithmic differential data, and means for creating volumes called data samples from said anti-logarithm which approximate said digital data samples while maintaining fidelity similar to said first fidelity.
Claim 2
Dependent Claim
136 words
A digital sampling keyboard instrument for encoding digital data samples having a certain number of bits representative of a particular musical sound having a first fidelity comprising: means for creating differences between successive ones of said digital data samples, means for creating the logarithm of said differences to form compressed logarithmic differential data which is compressed to a fewer number of bits than said certain number of bits, means for storing said compressed logarithmic differential data, means for adding time varying logarithmic encoded volume coefficients to said stored compressed logarithmic differential data to form added compressed logarithmic differential data, means for creating the anti-logarithm of said added compressed logarithmic differential data, and means for creating volumes called data samples from said anti-logarithm which approximate said digital data samples while maintaining fidelity similar to said first fidelity.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-01-21 | 1994-07-23 | 1995-01-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-01-21 | 1998-07-23 | 1999-01-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-01-21 | 2002-07-23 | 2003-01-22 | $7700.00 | Window Closed / Lapsed |