Dynamic bass equalization with modified sallen-key high pass filter
AssigneeLogitech Europe S.A.
InventorJeffrey S. Anderson
Life of this patent
Estimating the term…
Abstract
A dynamic bass equalization circuit has an amplitude dependent gain that is dependent upon the audio electrical signal amplitude and a dynamically adjusted frequency response that varies with the amplitude dependent gain. In one implementation, the dynamic bass equalization circuit includes a Sallen-Key high pass filter that includes an amplifier with a negative feedback path. The dynamically adjusted frequency response is provided by a parallel pair of reversed diodes connected in the negative feedback path.
Claims16
In a multimedia computer amplified speaker system having a speaker driver for transducing into sound through a bass speaker an audio electrical signal that has an amplitude, the improvement comprising:
- a dynamic bass equalization circuit with a second or higher order active filter having automatic dynamically adjusted gain and frequency response that vary with the amplitude of the audio electrical signal,
- the active filter including an amplifier with a negative feedback path which reduces a gain of said amplifier as said amplitude of said audio electrical signal increases such that the gain of a bass sound is produced by said bass speaker is reduced;
- and
- a low pass filter coupled to said bass equalization circuit that allows only bass signals to pass.
A speaker configured to receive an audio electrical signal that has an amplitude from a multimedia computer, comprising:
- a speaker housing;
- an electrical signal input;
- at least one treble band speaker;
- a sub-woofer speaker;
- a dynamic bass equalization circuit coupled between said electrical signal input and said sub-woofer speaker,
- a low pass filter coupled to said bass equalization circuit that allows only bass signals to pass,
- said dynamic bass equalization circuit including a second or higher order Sallen-Key high pass filter having a dynamically adjusted gain and frequency response that vary with the amplitude of the audio electrical signal,
- the active filter including
- an amplifier and
- a negative feedback path that includes a parallel pair of opposed diodes which reduce a gain of said amplifier as said amplitude of said audio electrical signal increases.
Dependencies are inferred from the claim text.