Parallel active noise reduction (ANR) and hear-through signal flow paths in acoustic devices

An active noise reduction (ANR) device comprising:

• one or more sensors configured to generate an input signal indicative of an external environment of the ANR device;
• an acoustic transducer configured to generate output audio;
• a first filter disposed in an ANR signal flow path of the ANR device, the first filter configured to process the input signal to generate a first signal for the acoustic transducer of the ANR device;
• and
• a pass-through signal flow path disposed in parallel with the ANR signal flow path, the pass-through signal flow path configured to generate a second signal for the acoustic transducer, wherein the pass-through signal flow path is configured to allow at least a portion of the input signal to pass through to the acoustic transducer in accordance with a variable gain associated with the pass-through signal flow path,
• wherein the acoustic transducer is driven by an output signal that is a combination of the first signal and the second signal.

One or more machine-readable storage devices having encoded thereon computer readable instructions for causing one or more processing devices to perform operations comprising:

• receiving an input signal captured by one or more sensors associated with an active noise reduction (ANR) device;
• processing the input signal using a first filter disposed in an ANR signal flow path to generate a first signal for an acoustic transducer of the ANR device;
• processing the input signal in a pass-through signal flow path in parallel with the ANR signal flow path to generate a second signal for the acoustic transducer, wherein the pass-through signal flow path is configured to allow at least a portion of the input signal to pass through to the acoustic transducer in accordance with a variable gain associated with the pass-through signal flow path;
• and
• generating an output signal for the acoustic transducer based on combining the first signal with the second signal.