ODESSA | Detmold
ODESSA III
Orchestral Blending and the Effect of Ensemble Sound at Different Perspectives
Hochschule für Musik | Detmold
Germany, November, 2019
Overview
Followed by the recordings of string orchestra at Montreal, and Geneva, the third ODESSA recording (Orchestral Distribution Effects in Sound, Space, and Acoustics) took place at Detmold concert house on the first VRACE workshop within a larger platform between ACTOR and VRACE project (Virtual Reality Audio for Cyber Environments). The ODESSA-III recording was conducted with a string ensemble consisting of 9 violins to investigate the orchestral blending effects, the effect of ensemble sound at different perspectives, etc. In addition to the recordings, the acoustic properties of the concert venues have been measured in this work using various techniques including impulse response, Spatial Decomposition Method (SDM), and acoustic camera recordings.
Along with the recording, a live listening test with 18 listeners also took place at Detmold concert house to investigate the predictability of the number of violins played, the blending between sound sources, and the impression of ‘ensemble sound’. To understand the influence of the room acoustics on these factors, the listeners were distributed to 5 different seating positions in the concert house (denoted as A, B, C, D, and E in figure), and the room acoustic conditions were varied using artificial reverberation introduced by the Wave Field Synthesis (WFS) system implemented in the Concert house. Along with that, the distribution of the sound sources on the stage was also varied in two different ways (violins pointing towards the listeners, and towards the back wall of the stage i.e. against the listeners) to know the influence of positions and orientations of musicians on the stage in the resulting sound field.
In each particular acoustic condition, a set of violins with a variable number of players (1, 2, 3, 4, 6, 9) have played at random order. In each take, two pieces of melodies are played: Symphony No.6 in B minor, I. Adagio – Allegro non troppo by Tchaikovsky (similar to ODESSA I, Subject 4), and Sonata No.12 in A-flat Major, II Scherzo by Beethoven. The test participants were requested to listen to the sound samples by closing their eyes to give the listening test ratings. Using the test responses, the variation of predictability of the number of violins with acoustic environments, the threshold of the number of violins needed for the emergence of ensemble sound, and the factors influencing the blending between sources were analyzed in this investigation.