Acoustics Testing and Measurement [VIDEO]

Loudspeakers are not a one-size-fits-all solution. A speaker designed for a concert hall must faithfully reproduce the sounds from the stage, while one used on a public bus needs to be reliably intelligible and robust enough to withstand environmental elements and potential vandalism. Considerable time and energy are dedicated to meticulously selecting the right materials, ensuring the loudspeaker performs optimally within its enclosure, and using appropriate accessories that do not interfere with sound quality. This is where proper testing and measurements become crucial.

Before a loudspeaker receives the green light for production and installation, it must undergo acoustic testing and measurement to confirm it performs as expected. Depending on its intended use, a prototype enclosure may be designed to replicate the specific location where it will be installed. The results of these tests are reviewed and help engineers make precise adjustments for the next iteration of the loudspeaker.

Sometimes, engineers don't need to design a new product from scratch but instead aim to improve an existing design. The same acoustic testing and measurement procedures used on a finished product can determine what needs enhancement.

So, what is the acoustic testing and measurement process like?

Acoustic Testing in a Full Sphere and What It Means

In the audio industry, it's common to measure a loudspeaker mounted on a baffle board. This setup measures the loudspeaker's acoustic radiation pattern over a half-sphere (2 pi steradians), corresponding to the general direction the loudspeaker cone faces. However, this method doesn't account for the sound emitted from the back and sides of the loudspeaker or how it will interact within the enclosure in which it will eventually be housed.

A full-sphere measurement captures acoustic radiation in all directions. Historically, performing such measurements was challenging and required an extreme amount of patience. The loudspeaker would be mounted in a system or cabinet and placed inside an anechoic chamber—a room designed to absorb sound completely. Engineers would tediously take sound measurements from hundreds or thousands of points by manually moving a microphone and mapping out the results to create a 3D sound map or point cloud. This process could take weeks or even months and was typically done by a third-party consultant, making it time-consuming and extremely expensive.

Today, that same level of testing can be performed in a matter of minutes using the Klippel Near Field Scanner. This autonomous system allows an engineer to place a loudspeaker—whether a large concert hall speaker or a small Bluetooth device—in the center of the robotic apparatus, program it, and press go. The Near Field Scanner then gathers measurements from 2,000 and 3,000 points in under 25 minutes.

Once the Near Field Scanner has finished collecting data, the engineer receives a detailed diagram showing how sound is emitted from the loudspeaker in all directions.

Why Acoustic Testing Data Matters

In loudspeaker design, data is paramount. Without it, engineers would be operating blindly. Acoustic testing data informs engineers about the necessary improvements to the current loudspeaker iteration. Tests can also be conducted on completed systems, allowing engineers, designers, and other project stakeholders to input that information into simulation software. This enables them to predict precisely how the loudspeaker system will perform in environments like theaters, casinos, or trains.

Acoustic tests and measurements allow OEM customers to understand how to integrate loudspeakers into their products to achieve the best sound quality. These tests also enable engineers and manufacturers to produce and deliver reliable, high-quality products to their customers. The data from these measurements can transform a speaker that sounds okay into one that sounds extraordinary.

How to Get Your Loudspeaker Tested

If your company is having a loudspeaker designed for a specific product or application, you should expect it to be thoroughly tested before production. After all, how else would you know you're receiving a reliable product? But what if you want to understand how your current system sounds in new housing or need full-sphere data to input into simulation software? This is where third-party R&D partners can assist.

We at MISCO, house some of North America's most advanced testing and measurement tools. Through our subsidiary, Warkwyn, we can collect highly detailed data for our customers.

The MISCO engineers can also design custom loudspeakers tailored to your needs. Our teams collaborate with yours to create a loudspeaker or complete system that meets the specific requirements of your project. We test products throughout the design process, ensuring you receive only the highest-quality product. As an original equipment manufacturer, once the design and testing are complete, we can put your loudspeaker into full production at our U.S.-based facility.

Need Further Assistance with Getting Your Loudspeaker Tested?

The MISCO team can assist you with any project and coordinate the testing and measurement of your product.

If you need a new loudspeaker for your product but are unsure if a custom solution fits within your budget, our team can help you select an existing loudspeaker from our extensive catalog. Every loudspeaker we manufacture must pass our strict end-of-line testing before it's shipped to you. We do this so you can expect reliable, high-quality products every time you order from us.

Contact us today to see how MISCO can help you.