High resolution acoustic metrology by combining high GHZ frequency ultrasound and scanning probe microscopy

In order to extract ever more performance from semiconductor devices on the same device area, the semiconductor industry is moving towards device structures with increasingly complex material combinations and 3D geometries. To ensure cost effective fabrication of next generation devices, metrology solutions are needed that tackle the specific...

Efficient and Stable Acoustical Coupling for GHz Subsurface Probe Microscopy

Many techniques are under development for the detection of subsurface defects or cracks. One such method is GHz subsurface probe microscopy (GHz SSPM). Here, modulated GHz elastic waves are transmitted through the bottom of a sample. The waves are scattered by buried features and detected using the probe of an atomic force microscope (AFM),...

Quantifying sound quality in loudspeaker reproduction

We present PREQUEL: Perceptual Reproduction Quality Evaluation for Loudspeakers. Instead of quantifying the loudspeaker system itself, PREQUEL quantifies the overall loudspeakers' perceived sound quality by assessing their acoustic output using a set of music signals. This approach introduces a major problem: subjects cannot be provided with an...

Underwater noise measurements in the North Sea in and near the Princess Amalia Wind Farm in operation

Sound Photographs to reveal vehicle pass-by sources with a calibrated source-strength level

In national and European discussions, it appears that the conventional sound measurement techniques are insufficient to answer some relevant questions with respect to source strength of road vehicles. An example of such a question is: What is the importance of tyre-road noise on the one hand and drive-line noise on the other hand in every day...

A- and C-weighted sound levels as predictors of the annoyance caused by shooting sounds, for various facade attenuation types

In a previous study on the annoyance caused by a great variety of shooting sounds [J. Acoust. Soc. Am. 109, 244-253 (2001)], it was shown that the annoyance, as rated indoors with the windows closed, could be adequately predicted from the outdoor A-weighted and C-weighted sound-exposure levels [ASEL (L(AE)) and CSEL (L(CE))] of the impulse...

On the assessment of shooting sounds: Loudness-level weightings versus A- and C-weighted sound exposure levels (L)

As an alternative to the A-weighted sound exposure level (ASEL) Schomer et al. [J. Acoust. Soc. Am. 110, 2390-2397 (2001)] used the equal-loudness level contours as a dynamic filter to determine the loudness-level-weighted sound exposure level (LLSEL). From their analyses they concluded that the LLSEL better orders and assesses traffic and...

Measuring TGV source strength with Syntacan

A 10 m high, vertical, synthetic acoustic antenna (Syntacan) has been used to measure the acoustic source strength and the vertical source distribution of a French TGV, as a function of the speed of the train, the frequency of the sound and the coach type (passenger coach, power car). The results are intended as input for calculation schemes and...

Measurements of structure-borne wave intensity on lightly damped pipes

Measurement of the structure-borne sound energy flow through pipes has been studied for the purpose of transmission path ranking. This paper describes the measuring methods for frequencies below the cut-off frequency of the n = 2 shell mode. The methods show a strong analogy with the two-microphone cross-spectral density method for airborne...

Noise emission type test methods for railbound vehicles at constant speed

ISO 3095 describes a type test method for noise emission of railbound vehicles at constant speed. The quality of this method is discussed on the basis of practical experience. It is shown that the method is not satisfactory and must be improved. Possibilities for such improvements are presented.

A new system for rating impact sound insulation

The rating of impact sound insulation on the basis of tapping machine measurements with the ISO reference values has proved to be unsatisfactory in practice. This is mainly due to the differences in spectrum shape of tapping machine noise and real life impact noises, such as walking. The problem can be solved by changing the reference values in...