A validation of high performance computation codes for large professional audio systems simulation

Nowadays the effectiveness of computation codes is indeed recognized in a variety of scientific and industrial applications. In particular, analyses pertinent to multibody systems, multiphysics and multiobjective optimization could not be dealt with without computation codes support. The possibility of designing components and/or whole systems in an efficient and cost-effective way will call for reliable simulation methods to tackle real industrial cases. Moreover, in case of vibroacoustic analysis these methods have to satisfy quite challenging requirements as being able to take into account large frequency ranges and big model sizes in a reasonable calculation time and represent very complex domains. This article intends to document the progress we have done lately to access the capabilities of commercially available computation methodologies in relation to large professional audio systems simulation. The very last techniques developed in LMS Virtual Lab code, i.e. the H-Matrix boundary element (H-Matrix BEM) and the FEM Adaptive Order (FEM AO) solvers, have been tested to simulate the far field acoustic directional characteristics of an Arrayable Loudspeaker's Horn in comparison with the full space far field measured Acoustic Balloon. The horn comprises a 4" dome compression driver, which represents the electroacoustic transducer, an acoustic waveguide and the horn itself. All the measurements were acquired at RCF Laboratory where a two axis fixture enables to collect a full acoustic Balloon overnight. Experimental test and simulated results are compared in order to validate the computational analysis. The whole simulation model is solved up to high audio frequencies (12.5 kHz) in a far field's Balloon grid of virtual microphones. Precise angular far field directivity measurements have been carried out by means of a state-of-the-art testing experimental set-up and good agreement with simulation results obtained in the frequency range of interest. The comparison with previous results obtained by the authors by means of other advanced analysis techniques as Fast Multipole BEM and FEM AML shows how the H-Matrix and FEM AO solvers allow to drastically speed-up computation time and reduce memory consumption for vibroacoustic uncoupled problems. As a general comment we can assert that the efficiency of all these tested methodologies allows to solve in a very satisfactory way otherwise unaffordable problems by means of standard approaches. Moreover, cluster arrays configurations have been also simulated in this application in order to test results accuracy and competitive solver times.