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This paper presents an on-line, order-based roughness approach for vehicle engine sounds. This new algorithm reconstructs the sound envelope per critical band in an analytical way from the order amplitudes, phases and frequencies. The most time-demanding operations of the classical roughness models are no longer needed, rendering the algorithm extremely fast and applicable in real-time. Another interesting characteristic of this new algorithm is the unique link which is established between the roughness and the engine order components of the sound. Sound engineers can easily identify which order components need to be modified to reduce a roughness problem.

15 years of NVH applications make Transfer Path Analysis appear a commodity tool. This is however not the case. Required insight in the application constraints makes TPA remain an expert approach. This paper reviews past progress in TPA methodology and its limitations. It then introduces a number of innovative approaches addressing these, opening new application fields. This includes speed improvement (Fast TPA), structural modeling integration (Modal Contribution Analysis), CAE integration (Hybrid TPA), sound quality interpretation (TPA-sound synthesis) and supporting better exploitation of operational data (Operational Path Analysis). An outlook is given to the next challenge, the application to transient problems.

Aircraft noise modeling aims to provide designers with computational tools that allow exploring the design parameters domain early in the design and development process. A number of modeling techniques are available for acoustics and vibration prediction, but in order to define objective targets for sound quality perception, dedicated tools are still needed to correlate structural models and design modifications with human perception of sounds. This paper presents a model-based sound synthesis concept for interior and exterior aircraft noise that allows interactive, real-time sound reproduction and replay. The proposed approach is presented through two application cases: jet flyover noise and turboprop interior noise.

The pressure on development cycles in the automotive industry forces the acoustical engineers to create awareness of sound quality in the early stages of development, perhaps even before a physical prototype is available. Currently, designers have few tools to help them listen to their “virtual” models. For the design of a synthesis platform of in-vehicle binaural sound, the sound should be modeled with almost identical sound quality perception. A concept is presented where the total sound of a vehicle is split in a number of components, each with its own sound characteristics. These characteristics are described in a signal model that allows the analysis of an existing sound into a limited number of signal components: orders-frequency spectra, time envelopes and time recordings.