ISEAT 2019 in China
Dates: November 9th - 10th 2019
More Information will follow soon!
1. Titel: Optimal Use of Software and Hardware Resources in Active Loudspeaker Design
Abstract: Increasing the efficiency and voltage sensitivity of the electro-acoustical conversion is the key to modern audio devices generating the required sound output with minimum size, weight, cost and energy. Traditional loudspeaker design sacrifices efficiency for sound quality. Nonlinear adaptive control can compensate for the undesired signal distortion, protect the transducer against overload, stabilize the voice coil position and cope with time-varying properties of the suspension. The paper presents a new design concept for active loudspeaker systems that uses the new degree of freedom provided by DSP to exploit a nonlinear motor topology, a soft suspension and modal vibration in the diaphragm, panel and in the acoustical systems.
2. Titel: Fast and Sensitive End-of-Line Testing
Abstract: Measurement time is a crucial factor for the total cost and feasibility of end-of-line quality control. This paper discusses new strategies minimizing the test time for transducers and audio systems while ensuring high sensitivity of defect detection, extracting comprehen-sive diagnostics information and using available resources in the best possible way. Modern production lines are fully automated and highly benefit from high speed testing. Optimal test stimuli and sophisticated processing in combination with multi-channel test design are the key factors for smart testing. Appropriate acoustical, mechanical and electrical sensors are discussed and suggested. Furthermore, parallel or alternating test schemes reduce the overall test time. Finally, typical concerns and pitfalls when testing at high speed are addressed and illustrated by measurement results.
3. Titel: Minimizing Costs in Audio Devices through Efficient End-of-line Testing
Abstract: Variances in the parts and uncertainties in the assembling process degrade the performance and the reliability of the manufactured devices. Defective units increase the manufacturing cost if detected during end-of-line testing or increase the after-sales cost if an undetected failure occurs in the field. This paper addresses the role of end-of-line testing to reduce both kinds of failures and to maximize the performance/cost ratio as seen by the end-user. The selection of sensitive and fast measurements, which can be performed under manufacturing condition, is the basis for the PASS/FAIL classification. The paper shows that optimal production limits used in EoL-testing minimize the overall cost by considering a clear product definition, information from the particular design, statistical data from manufacturing process and traceability of the field rejects. The general concept presented here is illustrated using practical examples from automotive and other applications.