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 Product Testing Capabilities
Our powerful product testing system allows us to measure, record, analyze, and evaluate sound and vibration levels coming from your product. We will assess each of the many sound sources and paths in a product, and develop the best solution for meeting your acoustic goals.
Sound Quality
We develop sound adjustment solutions that will enhance the end user's perceptions of the OEM's product quality or value. During this process we measure and evaluate a product's sound according to many parameters, not just the A-weighted sound level.
- Systems for sound recording
Our Head and Torso Simulator offers realistic sound recordings and sound level presentations.
- Hemi-Anechoic Room with Chassis Dynamometer for Vehicle Simulation.
Our Hemi-Anechoic room is large enough to test most buses, trucks, and medium sized off-highway machines. The chassis dynamometer can support axle weights up to 22,000 lbs and can create a load of over 600 HP
- Sound Quality Jury Room
Actual and simulated recordings of the sound from your product can be presented in our jury room for evaluation. Through this process, we can understand the parts of the sound that customers may find pleasing or undesirable.
- Sound file editing, playback and calculating metrics
Bruel and Kjaer's Pulse software is used for recording and analyzing the sound of products, for calculating the various sound metrics, and for simulating noise treatments during sound quality evaluations.
- Reverberation Room
A 7,000 cubic foot (200 cubic meter) chamber with hard, non-porous walls, ceiling and floor. A rotating sound wave diffuser provides a random incidence environment for performing Sound Transmission Loss (STL), sound absorption, and sound power testing. Two four by four foot test windows provide for vertical and horizontal STL measurements. A special feature of the room is an eight by eight foot "buck" or component test window which allows for very detailed analysis of large components such as a cab, floor or firewall. The large buck opening gives truck and off-highway vehicle manufacturers the opportunity to test complete systems without destroying the vehicle.
Noise Control Optimization
We develop models based on sound sources and paths within a product. As a model is developed, treatments are simulated and the optimum package is assembled. The cost and performance of each treatment is evaluated, and parts contributing little or no value to the product are eliminated.
- Full Machine Testing
Vehicles and machines can be tested in our hemi-anechoic room, reverberation room, or on our outdoor test pad.
- Component Testing
A vehicle front of dash, or other vehicle or machine components can be placed in our "buck" testing chamber. This 8' x 8' opening connects a quiet room with the reverberation chamber. The dash or component is then sealed in the opening so that sound from the reverberation room only enters the quiet room through the component. A sound intensity scan may then be performed to provide a level of detail not previously possible. This type of test provides a highly repeatable method for part development and optimization.
- Source Path Analysis
Source path analysis is a method of mapping noise sources by differentiating sound levels based upon the direction from which they originate using sound intensity. The source path analysis technique is used to determine appropriate treatments to reduce the airborne sound paths into a vehicle's interior, information regarding the contribution of each path to the interior sound level and the spectrum is required. Historically, this has been determined through windowing studies.
The Blachford Acoustics Department has developed alternate measurement method that combines sound intensity measurements with limited windowing. Here, the major noise paths are treated similar to the windowing process, but now the sound power of each open window is measured using sound intensity. The sound power is then propagated through the in- house modeling program to the receiver locations based on the in-cab room constant. By using this technique, the number of windowing treatments can be reduced, which significantly reduces the testing time. For more information on this topic, please refer to the paper Determination of In-Cab Sound Paths using Sound Intensity, written by Charles Moritz, Acoustics Engineering Manager, and Jason Kunio, Acoustics Engineer.
- Modeling
Using the source/path analysis technique a model rank ordering the contributions from each of the sound paths can be developed. From the model, the effect of various treatments can be evaluated and the optimum solution developed. Please refer to House Modeling Software Results for more information.
Sound Power
Sound power data is an absolute parameter, dependant only on the noise source itself, and independent of measurement environment. It is a quantity regulated by the European Community and other countries. Sound Power can be measured on our outdoor test pad, and inside our hemi-anechoic or reverberation chambers.
- Outdoor 10 meter diameter Test Pad for dynamic testing.
Sound power measurements can be made on our outdoor test pad located next to the laboratory. In addition to the 10 meter hemispherical test surface, acceleration and deceleration lanes are available.
- Reverberation Room
Sound power measurements can be made in our 200 cubic meter reverberation room according to various ANSI and ISO standards. This room contains rotating and stationary diffusers.
- Hemi-Anechoic Room
Sound power measurements can be made in our hemi-anechoic chamber according to various ANSI and ISO standards.
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