Audio Signal Control Circuit Dynamic Cutoff Adjustment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing audio signal amplifier devices are unable to dynamically adjust the cutoff frequencies of high-pass and low-pass filters according to the level of an audio signal, limiting their ability to optimize sound quality and balance.
Innovation Solution
An audio signal control circuit that generates an adjustment signal to dynamically adjust the cutoff frequencies of high-pass and low-pass filters by subtracting the adjustment signal from the audio signal for the high-range output and adding it to the audio signal for the low-range output, using a processor and bandpass filters to optimize frequency characteristics.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If the coefficient is fixed according to speaker specifications, then the amplifier device can maintain stable operation, but it cannot dynamically change the cutoff frequencies of the HPF and LPF according to the audio signal level
Solution Approach 1:
An adjustment signal is introduced as an intermediary element that mediates between the audio signal and the filter outputs. This adjustment signal, generated by extracting a specific frequency band from the audio signal, is added to the LPF output and subtracted from the HPF output, thereby dynamically adjusting the cutoff frequencies without requiring complex variable filters
Solution Approach 2:
The patent replaces the mechanical approach of using variable filters (which would require complex mechanical or electronic tuning mechanisms) with a signal processing approach. By using simple adders and subtractors to combine the adjustment signal with the filter outputs, the system achieves dynamic cutoff frequency adjustment without mechanical moving parts or complex electronic tuning circuits
2Adaptability or versatility
If variable filters are used to dynamically adjust cutoff frequencies, then the audio signal level can be adapted, but the circuit complexity and resource usage increase
Solution Approach 1:
The audio signal is segmented into different frequency components, with the adjustment signal being a specific frequency band extracted from the original audio signal. This segmentation allows the system to manipulate only the relevant frequency components needed for cutoff frequency adjustment, rather than processing the entire audio spectrum through complex variable filters
Solution Approach 2:
Instead of modifying the original audio signal directly through complex variable filters, the patent creates a copy of the audio signal in the form of the adjustment signal. This copy is then processed and combined with the original signal paths, achieving the desired frequency separation effect without altering the original signal or requiring complex filter modifications
Data Source
AI summary
An audio signal control circuit includes an adjustment signal generator that extracts a frequency band, which includes a frequency at which a frequency band shared by a low-range speaker and a frequency band shared by a high-range speaker overlap each other, to generate an adjustment signal Sck; a high-range outputter that subtracts the adjustment signal Sck from an audio signal Sa to generate a high-range audio signal SaH and outputs it to a high-pass filter; and a low-range outputter that adds the adjustment signal Sck to the audio signal Sa to generate a low-range audio signal SaL and outputs it to a low-pass filter.