Patent · US Expired

Back-masking effect generator

US5245663A · kind A · utility

5Cited by
2References
19Claims
0Family size

Inventor

Key dates

Filing dateMay 28, 1992
Grant dateSep 14, 1993
Priority date
Expiry dateMay 28, 2012

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04K2203/12
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

The invention comprises a back-masking effect generator which produces, almost in real time, the simulated sound of an input audio signal being reproduced in reverse. The device digitally records the sound in packets of short duration with alternating packets being written to first and second static random access memory devices, respectively. After an initial state in which the first memory device is filled with the digitized input audio signal, the generator then continuously alternates between two other states. In one state, the second memory device is filled while the first memory device is simultaneously emptied to a digital-to-analog converter in the reverse order from which it was filled. In the other state, the first static random access memory is filled while the second memory device is simultaneously emptied to the digital-to-analog converter.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.