摘要:
To improve the reproduction of audio signals, the signal components of a selected audio frequency range (1) of an audio signal are concentrated in a narrower audio frequency range (II). This is achieved by detecting first signal components in the first audio frequency range (I), generating second signal components in the second audio frequency range (II), and controlling the amplitude of the second signal components in response to the amplitude of the first signal components. As a result, dedicated transducers may be used which are particularly efficient in the narrower frequency range. The original frequency range (I) may contain the lower frequency signal components (bass components) of the audio signal.
摘要:
A device (1) is arranged for adjusting the amplitude of an audio signal (x) such that the output of a transducer (2) coupled to the device is equivalent to the output of a reference transducer. The device comprises a first simulation unit (11) for producing a reference signal (y) in response to the audio signal (x), a second simulation unit (12) for producing a further signal (z) in response the audio signal (x), and comparator means (15) for comparing the reference signal (y) and the further signal (z) so as to produce an adjustment signal (a) which is fed to an adjustment unit (10). The first simulation unit (11) simulates the response of a reference transducer, while the second simulation unit (12) simulates the response of the actual transducer (2) to the audio signal (x).
摘要:
An audio signal may be enhanced by adding enhancement signals, such as harmonics and/or sub-harmonics of the signal's bass components. To avoid any unwanted enhancement signals during soft passages or speech, it is proposed to monitor the audio signal for tonal signal components in a frequency range and to only add the enhancement signals if such tonal signals are detected. A tonal detector (3) may comprise sine and cosine generators whose frequency is preferably equal to a dominant frequency of the frequency range.
摘要:
A sound massage system (1) comprises a sound device (3) arranged for producing a rotating sound beam, a vibration element (5) arranged for producing vibrations, wherein the vibration frequency is less than 300 Hertz, and a control unit (7) arranged for controlling the sound device (3) and the vibration element (5). The sound massage system provides imitation of the Tibetan signing bowls. The invention also related to a relaxation system comprising the sound massage system.
摘要:
A cooling device (1) using pulsating fluid for cooling of an object, comprising: a transducer (2) having a membrane adapted to generate pressure waves at a working frequency (fw), and a cavity (4) enclosing a first side of the membrane. The cavity (4) has at least one opening (5) adapted to emit a pulsating net output fluid flow towards the object, wherein the opening (5) is in communication with a second side of the membrane. The cavity (4) is sufficiently small to prevent fluid in the cavity (4) from acting as a spring in a resonating mass-spring system in the working range. This is advantageous as a volume velocity (u1) at the opening is essentially equal to a volume velocity (u1′) at the second side of the membrane, apart from a minus sign. Thus, at the working frequency the pulsating net output fluid can be largely cancelled due to the counter phase with the pressure waves on the second side of the membrane resulting in a close to zero far-field volume velocity. Thus a low sound level is achieved, at a low cost, without requiring mechanical symmetry.
摘要:
An apparatus for use as an output device of a user interface to an information processing system includes at least one device for generating a synthetic jet. The device is capable of producing outputs with different modalities. Examples of different modalities that are possible include airflows, vibration and sound.
摘要:
An audio driver including a diaphragm with a first side and a second side. The diaphragm is coupled to a transducer element on the second side and is arranged to radiate sound. The transducer element converts an electrical input signal into movement of the diaphragm. The diaphragm is arranged such that a part of the diaphragm at least partly forms a cavity at the second side of an air conduit is coupled to the cavity. The air conduit has a first opening into the cavity and a second opening outside of the cavity. The air conduit and cavity form a resonator which has a resonance frequency that is less than half a free air acoustic resonance frequency of the audio driver.
摘要:
A loudspeaker system includes at least two stand-alone loudspeaker devices (1L, 1R) each comprising a frame (3) provided with a vertically oriented array (5) of first loudspeakers (7) for reproducing sound in a higher frequency range. The system further includes a second loudspeaker (13) for reproducing sound in a lower frequency range, wherein the frequency ranges have a crossover frequency fc and 750 Hz
摘要:
A vacuum cleaning device comprises a unit (1) for aerodynamically affecting dust particles and/or a surface (40) to be cleaned in order for the particles to become dislodged from the surface (40) and to be received by the unit (1). The unit (1) comprises a housing (10) having an internal space (11) enclosed by a housing wall (12) in which at least one opening (13) is arranged, a movable surface (30) which is integrated in the housing wall (12), and means (31) for actuating the movable surface (30), which are adapted to realize an oscillating movement of the surface (30) that causes air to alternately be drawn into the housing (10) through the opening (13) and expelled from the housing (10) through the opening (13). At least a portion of the housing wall (12), particularly a portion of the housing wall (12) in which the opening (13) is located, is movably arranged in the unit (1).
摘要:
A device (30) for adapting an audio input signal (V1n) to a transducer unit (20) comprises: mapping means (10) for mapping input signal components from a first audio frequency range onto a second audio frequency range so as to produce a mapped audio signal (VM), wherein the second audio frequency range is narrower than the first audio frequency range, and wherein the transducer unit (20) has a maximum efficiency at the second audio frequency range, filter means (31) for filtering the input signal (V1n) so as to produce a filtered input signal (V1n′) having a third audio frequency range, and combination means (32) for combining the mapped audio signal (VM) and the filtered input signal (V1n′) so as to produce a transducer signal (VT). The first audio frequency range is preferably contained in the second audio frequency range, while the third audio frequency range may be adjacent the first audio frequency range. The second audio frequency range preferably extends within 5% of the Helmholtz frequency of the transducer unit (20).