Abstract: A method of recording ambisonic sound fields with a spatially distributed plurality of ambisonic microphones comprising a step of recording sound signals from plurality of ambisonic microphones a step of converting recorded sound signals to ambisonic sound fields and a step of interpolation of the ambisonic sound fields according to the invention comprises a step of generating synchronizing signals for particular ambisonic microphones for synchronized recording of sound signals from plurality of ambisonic microphones and during the step of interpolation of the ambisonic sound fields it includes filtering sound signals from particular microphones with individual filters having a distance-dependent impulse response having a cut-off frequency fc(dm) depending on distance dm between point of interpolation and m-th microphone applying gradual distance dependent attenuation applying re-balancing with amplification of 0th ordered ambisonic component and attenuating remaining ambisonic components.

Abstract: The invention concerns an audio signal encoding method comprising the steps of: collecting the audio signal samples, determining sinusoidal components in subsequent frames, estimation of amplitudes and frequencies of the components for each frame, merging thus obtained pairs into sinusoidal trajectories, splitting particular trajectories into segments, transforming particular trajectories comprising of their amplitude and frequency variations to the frequency domain by means of a digital transform performed on segments longer than the frame duration, quantization and selection of transform coefficients in the segments, entropy encoding, and outputting the quantized coefficients as output data. The method is characterized in that the length of the segments into which each trajectory is split is individually adjusted in time for each trajectory.

Abstract: The invention concerns a microphone probe having a body being substantially a first solid of revolution with a number of audio sensors distributed thereon and located in the recesses. The recesses have substantially a shape of a second body of revolution with an axis of symmetry perpendicular to the surface of the body. The sensors are connected to an acquisition unit, that delivers audio signals to the output. The audio sensors are digital audio sensors comprising printed circuit board with MEMS microphone element mounted thereon, wherein MEMS microphone element is mounted on the side of the printed circuit board facing the inner side of the body, so that the sound reaches MEMS microphone element via recess and opening. The depth of recesses is in a range between 3 and 20 mm. The acquisition unit has a clocking device determining common time base for audio sensors.