Custom-made loudspeakers blend art and science. The art lies in selecting materials and applying design techniques to achieve precise audio performance. The science involves rigorous testing to confirm the speaker meets its intended performance criteria.
Manufacturers primarily rely on two powerful tools for testing loudspeakers: anechoic chambers and Klippel Near Field Scanners (NFS). Both tools measure the speaker's acoustic radiation pattern and frequency response from multiple points and angles. Let's explore how these tools compare.
Anechoic Chambers
Developed in the 1930s, anechoic chambers are soundproof environments designed specifically for acoustical testing without interference. These chambers feature thick, insulated walls that block external noise and internal surfaces lined with absorptive cones or wedges to prevent acoustic reflections. "Anechoic" means echo-free. Constructing these chambers is costly and requires significant space, often exceeding half a million dollars.
During testing, speakers are attached to a tri-axis gimbal, rotating 360°, while measurements are taken by a stationary microphone positioned at a set distance.
Klippel Near Field Scanner
The Near Field Scanner, developed by Klippel, a renowned German audio testing company, integrates robotics and advanced software. Instead of rotating the speaker, a microphone moves around the fixed speaker, capturing detailed acoustic data. View the video below to see the scanner in action.
This scanner is particularly adept at evaluating devices whose acoustic performance varies significantly across different angles and listening positions, such as professional concert systems, portable Bluetooth speakers, tablets, and laptops.
The Near Field Scanner system costs approximately $100,000—significantly less expensive than building a new anechoic chamber. Its portability offers significant advantages, making it far more flexible than stationary anechoic chambers.
Anechoic Chamber vs. Near Field Scanner: Key Differences
A notable limitation of anechoic chambers is their inability to accurately measure very low frequencies due to spatial constraints. For example, a 100Hz sound wave measures approximately 11 feet, while a 20Hz wave extends around 60 feet. Such large-scale measurements typically require immense chambers, generally available only in major corporations or government facilities. Smaller chambers often supplement their measurements with outdoor testing, though weather conditions must be optimal to ensure accuracy.
Conversely, the Near Field Scanner effectively overcomes these spatial constraints. Operating in standard rooms with a microphone positioned within the speaker’s "near field" (approximately 10-15 cm away), it captures extensive data points to generate a complete 360° radiation pattern. Klippel's sophisticated software then extrapolates this data to simulate far-field acoustic responses, resolving low-frequency measurement challenges.
Efficiency is another significant advantage of the Near Field Scanner. Its automated robotics system swiftly collects thousands of data points, allowing technicians to engage in other tasks concurrently. Collecting comparable data using an anechoic chamber would require extensive dedicated labor.
Maximizing Technology
At MISCO, we harness Klippel’s Near Field Scanner and additional cutting-edge technologies to rapidly develop and refine loudspeaker prototypes. Our final products undergo rigorous testing to guarantee they meet or exceed customer expectations.
Partner with MISCO for Advanced Loudspeaker Testing and Custom Solutions
Selecting the ideal loudspeaker demands expert audio engineering coupled with reliable performance verification. At MISCO, we employ advanced testing technologies like the Anechoic Chamber and Klippel Near Field Scanner, ensuring every loudspeaker adheres to stringent quality standards.
Whether your needs include custom-engineered loudspeakers or guidance in audio system design, MISCO's experienced team is ready to assist. With over 75 years of industry expertise and state-of-the-art facilities, we are dedicated to delivering superior audio solutions.
Ready to enhance your project's audio? Contact MISCO today and discover how our commitment to innovation and precision can elevate your sound.
