Audio enhancement system

Abstract

A stereo enhancement system processes the difference signal component generated from a pair of left and right input signals to create a broadened stereo image reproduced through a pair of speakers or through a surround sound system. Processing of the difference signal component occurs through equalization characterized by amplification of the low and high range of auditory frequencies. The processed difference signal is combined with a sum signal, generated from the left and right input signals, and the original left and right input signals to create enhanced left and right output signals.

Description

[0001] This application is a continuation of prior application Ser. No. 10 / 614,623, filed Jul. 7, 2003, which was a continuation of prior application Ser. No. 09 / 211,953, filed Dec. 15, 1998, now U.S. Pat. No. 6,597,791, issued Jul. 22, 2003, which was a continuation of U.S. application Ser. No. 08 / 770,045, filed Dec. 19, 1996, now U.S. Pat. No. 5,892,830, issued Apr. 6, 1999, which was a continuation of U.S. application Ser. No. 08 / 430,751, filed Apr. 27, 1995, now U.S. Pat. No. 5,661,808, issued Aug. 26, 1997, the entirety of which is incorporated by reference.FIELD OF THE INVENTION [0002] This invention relates generally to audio enhancement systems, and especially those systems and methods designed to improve the realism of stereo sound reproduction. More particularly, this invention relates to apparatus for broadening the sound image created from amplification of stereo signals through a pair of loudspeakers, without introducing unnatural phase-shift or time-delays within the s...

AI Technical Summary

Benefits of technology

"The present invention is an improved stereo enhancement system that creates a wider sound image. This system is designed to work with low-power audio devices and has a simple circuit structure. The system uses a set of sum and difference signals to enhance the frequency components that are statistically of low-intensity. The equalization of the difference signal is done without inappropriately boosting the corresponding mid-range frequency components. The enhancement system is particularly desirable for audio systems that are inexpensive, operate with low-power output signals, and have limited space for incorporating an enhancement system."

Problems solved by technology

In addition, amplification or enhancement of such digitally-stored sound may tend to overdrive computer audio amplifiers or computer speakers, which may be relatively “low-power” devices.

This concern is particularly relevant in the lower, i.e., bass, frequencies where over-amplification can cause amplifier “clipping,” and may severely damage the low-power speakers of computer systems or television sets.

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