Disclosed is an ambulatory infusion device, including a control unit and an electroacoustic transducer. The control unit is configured to operate the electroacoustic transducer as noise emitter or to operate the electroacoustic transducer as noise receiver and to determine from a received noise that is received by the electroacoustic transducer a state of the ambulatory infusion device.

According to this method, the playback level of the music is measured as compared to a reference level and if the playback level is lower than the reference level the level of the low frequencies is increased in a manner substantially proportional to the difference between the reference level and the measured level to maintain the tonal balance of the musical piece.

An audio speaker system includes: an amplifier, where a positive input terminal of the amplifier is configured to be coupled to a first reference voltage node; and a piezo diaphragm including: a metal plate; a first piezo film attached to the metal plate, where the first piezo film is configured to function as a speaker during operation of the audio speaker system; and a second piezo film attached to the metal plate and spaced apart from the first piezo film, where the second piezo film is configured to function as a microphone during operation of the audio speaker system, where an output terminal of the amplifier is coupled to the first piezo film, and where a negative input terminal of the amplifier is coupled to the second piezo film.

A screen sound production component is disposed on a back side of a screen. Based on a user having a high requirement for a sound receiving effect, a high requirement for confidentiality of sound content, or a high requirement for sound quality, the mobile terminal depends on the screen sound production component to drive the screen to vibrate, so as to produce sound, that is, the mobile terminal uses a privacy mode. In the privacy mode, a location at which the screen produces sound is close to the ear of the user. Therefore, it can be ensured that the user directly receives a large amount of sound produced by the screen, instead of mainly receiving sound by using a sound output hole on the mobile terminal.

Example embodiments may include one or more of receiving an electrical sound emission signal from a sound controller, interrupting reception of the electrical sound emission signal, by a sound emission interruption circuit connected to a sound emitter, and receiving an electrical ambient sound signal via a sound detection circuit, based on ambient sound sensed by the sound emitter when the reception of the electrical sound emission signal is interrupted by the sound emission interruption circuit.

Methods for rendering audio for playback by two or more speakers are disclosed. The audio includes one or more audio signals, each with an associated intended perceived spatial position. Relative activation of the speakers may be a cost function of a model of perceived spatial position of the audio signals when played back over the speakers, a measure of proximity of the intended perceived spatial position of the audio signals to positions of the speakers, and one or more additional dynamically configurable functions. The dynamically configurable functions may be based on at least one or more properties of the audio signals, one or more properties of the set of speakers and/or one or more external inputs.

Disclosed are an electronic device and method for detecting the proximity of an object. In an embodiment, the electronic device includes a communication module, a sound emitter, a sound receiver, and a processor. The processor receives at least one part of a voice signal from a calling party through the communication module, and determines whether there is a voice idle time in the at least one part of the voice signal. When the voice idle time is present in the at least one part of the voice signal, the processor outputs a sound wave in an inaudible frequency band through the sound emitter during the voice idle time. Then the processor receives, through the sound receiver, sound wave in the inaudible frequency band reflected from an object. Next, the processor may detect whether the object is proximate to the electronic device using the reflected sound wave in the inaudible frequency band.

An omnidirectional electroacoustic transducer capable of reproducing a sound with high acoustic quality and sufficient sound volume in a wide frequency band is provided with a small number of components. The electroacoustic transducer includes: two or more electroacoustic transduction units each including an electroacoustic transduction film and an elastic supporter, the electroacoustic transduction film having a polymer composite piezoelectric body in which piezoelectric body particles are dispersed in a viscoelastic matrix formed of a polymer material having viscoelasticity at a normal temperature, and two thin film electrodes laminated on both surfaces of the polymer composite piezoelectric body, and the elastic supporter being disposed to be closely attached to one principal surface of the electroacoustic transduction film so as to cause the electroacoustic transduction film to be bent, in which the two or more electroacoustic transduction units are disposed so that the electroacoustic transduction films face outward and form some or all of faces of a polyhedron.

A nonlinear control system and a speaker protection system are disclosed. In particular, a control system for adapting an audio output from a speaker in the proximity of an object is disclosed. The controller is configured to accept one or more input signals, and one or more estimated states produced by the model to produce one or more control signals. A speaker protection system and a quality control system are disclosed. More particularly, a system for clamping the input to a speaker dependent upon an estimate of the proximity, acoustic volume, and/or acoustic coupling of the speaker to a nearby object is disclosed.

In accordance with embodiments of the present disclosure, a device may include a piezoelectric speaker for generating sound, a microphone, and a controller communicatively coupled to the speaker and the microphone. The controller may be configured to receive a first signal from the piezoelectric speaker, the first signal induced at least in part by sound incident on the speaker other than sound generated by the piezoelectric speaker, receive a second signal from the microphone, the second signal induced by sound incident on the microphone, process at least one of the first signal and the second signal to determine at least one characteristic of sound incident upon at least one of the piezoelectric speaker and the microphone, and select at least one of the microphone and the piezoelectric speaker as a signal source for incident sound based on the at least one characteristic.