Produkt-Neuheit

Increasing requirements for noise and consumer protection are leading to a steady tightening of directives (e.g. EU Noise and Machinery Directives) with regard to the mandatory specification of the sound power level as a standardized comparative value for product-relevant sound emissions, combined with an increasing demand for high-performance acoustic measurement and testing technology.

At the same time, the importance of acoustic product optimization through sound design is growing.

Product sound design can be found in a wide range of noise-relevant industrial products.
The main focus here is on safety, comfort, well-being and marketing.
The aim is to use product sounds to make information, emotions and a certain brand image audible.

In addition to functionality and appearance, the sound of a product plays an important role. Psychoacousticians study the effects of noises and sounds on people, while sound designers use this as a basis for creating the sound world around a product.

At the same time, it is important to create brand-specific sounds for certain products, e.g. in the electric car sector, for reasons of safety.

The necessary analyses for the purpose of noise protection or product sound design can only be realized with special measuring methods and powerful testing technology.

Enveloping surface methods, which use sound power hemispheres (SLH) to enable acoustic measurements on test objects placed under a dome, are essential here. The sound power emitted by a noise source is measured at defined, statistically evenly distributed measuring points on a dome-shaped measuring surface that surrounds the source. The microphone/sensor positioning is based on sound power standards.

The optimized MTG hemispheres enable sound power measurements in accordance with the current 3744 and 3745 standards. The portfolio includes two different sizes with radii of 1 or 2 m (SLH 112 / SLH 212), which can be installed quickly and easily with 6 or 12 struts. 10 or 20 half-inch measuring microphones can be used in accordance with the DIN IEC 61094 standard.

Depending on the measurement task, the SLH can be equipped with standard measurement microphones, particularly low-noise measurement microphones or measurement microphones for harsh environments.

A standard-compliant, geometrically exact alignment to the center is possible without the use of additional measuring/adjustment equipment.

The SLH are designed as measurement microphone accessories for use in free-field half-space and for short outdoor applications without the influence of rain, wind or dust.

They are ideally suited for sound power measurements on various acoustically relevant components, such as vehicle components through to the measurement of tire noise.

The hemispheres made in Gefell are an "all for one" solution, whereby the user can also use suitable sensors from other manufacturers.

Unique in terms of flexibility is the ability to cover all relevant frequency ranges (DIN EN ISO 3745:2017-10 / "General case"). Synergies from MTG's development of 3D measurement microphone arrays for time-delayed three-dimensional recordings were helpful in the design and construction.

The design and construction are based on further developed, laser-cut, flat, sound-optimized light metal rail profiles, highly stable connecting elements and freely adjustable microphone holders.

The revised design ensures even better, stable sensor positioning, cost-effective, simplified assembly and measurement procedures and, last but not least, precisely reproducible measurement data in accordance with international standards. Based on practical experience, a number of components have been further developed, such as the horizontal connecting floor struts, vibration-damping floor stabilization pads and the stabilizing horizontal and diagonal tension cable bracing, which is important, for example, for use on test stands with clamping fields in the automotive sector.