A method and device for masking noise from a dialysis machine, as an example of a medical device, includes tubing or a fluid container, or both, being connectable to a patient for flowing fluid to or from the patient, and one or more sensors configured to detect one or more patient parameters. The dialysis machine further includes a controller configured to determine a sleep state of the patient based on the one or more patient parameters detected by the plurality of sensors, and adjust a masking sound in response to the sleep state of the patient. The masking sound is activatable in response to noise generated during operation of the dialysis machine.

Disclosed is an active-noise control device including two passive attenuation earphones each provided with an external microphone, an internal microphone and a loudspeaker. The control device includes a first processing chain having a feedforward filter, a feedback filter and a reconstruction module. The control device includes a second processing chain having a sound source identification module, said second processing chain being implemented in parallel with the first processing chain, and being suitable for parameterizing the first processing chain.

A noise reducing device includes: an acoustic-to-electric conversion section for collecting noise and outputting an analog noise signal; an analog-to-digital conversion section for converting the analog noise signal into a digital noise signal; and a digital processing section for generating a digital noise reducing signal on a basis of the digital noise signal and a desired parameter. The device further includes: a retaining section for retaining a plurality of parameters corresponding to a plurality of kinds of noise characteristics; a setting section for setting one of the plurality of parameters as the desired parameter of the digital processing section; a digital-to-analog conversion section for converting the digital noise reducing signal into an analog noise reducing signal; and an electric-to-acoustic conversion section for outputting noise reducing sound on a basis of the analog noise reducing signal.

A noise reducing device includes: an acoustic-to-electric conversion section for collecting noise and outputting an analog noise signal; an analog-to-digital conversion section for converting the analog noise signal into a digital noise signal; and a digital processing section for generating a digital noise reducing signal on a basis of the digital noise signal and a desired parameter. The device further includes: a retaining section for retaining a plurality of parameters corresponding to a plurality of kinds of noise characteristics; a setting section for setting one of the plurality of parameters as the desired parameter of the digital processing section; a digital-to-analog conversion section for converting the digital noise reducing signal into an analog noise reducing signal; and an electric-to-acoustic conversion section for outputting noise reducing sound on a basis of the analog noise reducing signal.