Systems and methods for creating a digital audio filter, such as an impulse response filter, using a pickup audio signal provided to an instrument signal capture device and a microphone signal provided to a mobile device are disclosed. In one embodiment, a method includes capturing a first audio signal using a signal capture device, performing frequency analysis on the digitized first audio signal to generate a frequency response spectrum representation, transmitting the frequency response spectrum representation of the first audio signal from the signal capture device to a mobile device, capturing a second audio signal using a microphone on the mobile device, performing frequency analysis on the at least one digitized second audio signal using the mobile device to generate a frequency response spectrum representation, and generating a digital audio filter from the frequency response spectrum representations of the first audio signal and the second audio signal.

An adaptive dynamic audio hum extractor eliminates line frequency hum components and associated higher harmonics from an audio signal. An audio signal containing line frequency hum can be processed by providing dynamically controlled notch filters at the fundamental line frequency and additional harmonic multiples of the fundamental frequency. The audio signal is detected to provide dynamic control of the depth of the notch filters. Alternatively, an audio signal containing hum can be processed by dividing the spectrum into at least two frequency bands, an unaltered high band combined with a dynamically processed low band. The adaptive dynamically controlled notch filters vary the depth of the notches in relation to the envelope or time averaged level of the bandwidth limited audio signal. This allows masking of the hum components with higher levels of audio, thereby providing transparency devoid of audio path notches.

An adaptive dynamic audio hum extractor eliminates line frequency hum components and associated higher harmonics from an audio signal. An audio signal containing line frequency hum can be processed by providing dynamically controlled notch filters at the fundamental line frequency and additional harmonic multiples of the fundamental frequency. The audio signal is detected to provide dynamic control of the depth of the notch filters. Alternatively, an audio signal containing hum can be processed by dividing the spectrum into at least two frequency bands, an unaltered high band combined with a dynamically processed low band. The adaptive dynamically controlled notch filters vary the depth of the notches in relation to the envelope or time averaged level of the bandwidth limited audio signal. This allows masking of the hum components with higher levels of audio, thereby providing transparency devoid of audio path notches.

A signal processing device acquires information relating to a stringed instrument, and sets a parameter to an equalizer based on the acquired information relating to the stringed instrument.

A signal processing device acquires information relating to a stringed instrument, and sets a parameter to an equalizer based on the acquired information relating to the stringed instrument.