In this paper the authors present an approach for two-dimensional sound reproduction using a circular layout of speakers where the gains are obtained from a variable polar pattern. The method presented here has the ability to be variable-order whilst keeping the same key features of a base polar pattern. Comparisons are drawn between the new approach and a previous approach by the authors using variable-order, variable-decoder Ambisonics. The new method is found to not be as directional as the Ambisonics approach, yet it maintains the base polar pattern unlike with Ambisonics. Whilst both approaches have two variable parameters the new approach’s parameters are independent and are therefore intuitive to an end user using such a tool as a spatialisation effect as well as technique.

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In recent years multisampled drum workstations have become increasingly popular. They offer an alternative to recording a full drum kit if a producer, engineer or amateur lacks the equipment, money, space or knowledge to produce a quality recording. These drum workstations strive for realism, often recording up to a hundred different velocity hits of the same drum, including recordings from all microphones for each drum hit and including bleed between these microphones. This paper describes research undertaken to investigate if it is possible to simulate the snare and kick drum bleed into the tom-tom microphones and the subsequent resonance of the tom-tom that is caused, with the aim of reducing the amount of audio data that needs to be stored. A listening test was performed asking participants to identify the real recording from a simulation. The results were not statistically significant to reject the hypothesis that subjects were unable to distinguish the difference between the real and simulated recordings. This suggests listeners were unable to identify the real recording in the majority of cases.

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Dynamic range compression is a nonlinear audio effect that reduces the dynamic range of a signal and is frequently used as part of the process of mixing multi-track audio recordings. A system for automatically setting the parameters of multiple dynamic range compressors (one acting on each track of the multi-track mix) is described. The perceptual signal features loudness and loudness range are used to cross-adaptively control each compressor. The system is fully autonomous and includes six different modes of operation. These were compared and evaluated against a mix in which compressor settings were chosen by an expert audio mix engineer. Clear preferences were established for the different modes of operation, and it was found that the autonomous system was capable of producing audio mixes of approximately the same subjective quality as those produced by the expert engineer.

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