Skip to main content

Directionally Optimised Representation of Musical Instruments


The DOREMI project has had as goals the performance of multi-channel recordings to be used for auralisation purposes, the evaluation of these auralisations and the study of further applications of the recording and reproduction method. In its first stage the project concentrated in the study of the directivity of different musical instruments and their representation using diverse types of recording setups. The second part of the project concentrated on the development of room auralizations using the multi-channel recordings of the first part of the project and their evaluation by means of listening tests. The final stage of the project focused on the development of different activities that could be linked with technical applications and further developments in a long-term project. The achievements of the project have been: - The implementation of a multi-channel recording system for musical instruments that improves the existing directivity representations, - A detailed description of the directivity of musical instruments in a performance situation to be compared with the traditional directivity descriptors, and - A study of different applications of the developed multi-channel recording system in the context of a long-term project. As regards the first goal of the project, the results fulfilled the expectations. The multi-channel system was implemented and the directivity representation of musical instruments in auralisations was improved. Results of listening tests, which used different amounts of virtual sources, showed that the multi-source representation in the auralisations improved considerably the sound quality in terms of naturalness of timbre of the instruments when the amount of virtual sources was increased. The optimisation of the system according to the best representations in the auralisations showed that the best representations were those that considered more virtual sources. It was also shown by the results of the listening tests with auralizations that the optimised representation had a better sound quality than the ones with the traditional fixed directivity representation. These improvements were mostly in the naturalness of timbre of the reproduced sound. As to the results corresponding to the second goal of the project, the directivity of different musical instruments was measured using two different methods, fulfilling the original goals of the project. The achievement concerning this goal was a detailed directivity representation of tones for multiple musical instruments, which could be visualised through a computer program created for this purpose. A complete description of the evolution of the directivity of the studied musical instruments can now be mapped and achieved certainly. The goal of achieving an averaged directivity of each of the studied instruments to be compared with the optimised representation using the method was also reached, as documented before. As regards the results and achievements of the last goal of the project, it can be stated that these were many and diverse. The first achievement of this stage is represented by multi-channel recordings of a duo of musical instruments with the proposed method; auralisations were built to assert the quality of the recording system. The auralizations showed that, as with single instruments, there was a clear improvement in the quality of the reproduced sound in terms of naturalness of timbre and the distinctiveness of the individual sources. A second result of the last part of the project was the viability of using studio non-anechoic recordings of the piano with the proposed method in room auralisations. It was shown that the studio recordings could be used to build auralisations and that the number of sources could be related with the quality of the reproduced sound in terms of timbre naturalness. An achievement of this part is therefore that it has shown that non-anechoic recordings can clearly be used as a basis for auralizations for sources that can hardly be recorded in an anechoic chamber. The third result of this part of the project proved a connection could be made between the multi-channel recordings and the achievement of an impulse response of musical instruments to be used for an alternative source representation, as it is La Timee. The fourth result of the last part of the project demonstrated that studio multi-channel recordings could be used as a basis to create a type of stereo recording mix that could bring an alternative timbre to the one done with traditional stereo techniques.