An ongoing debate in audio circles is: Are bigger speakers always better? They are certainly easier to build from a design standpoint. If you’re trying to fill an arena with sound everything can be huge—the speaker enclosures, the drivers inside them, and the electricity bill to create that much sound. However, most industries have much tighter space limitations and are always looking for ways to include speakers in final products that are smaller, louder, and sound better than the last generation.
It takes exceptional engineering and know-how about audio and physics to push the limits and shrink systems without sacrificing sound quality or volume.
Why Smaller Speakers Take More Thinking
To create soundwaves, a speaker changes electrical energy into mechanical energy in the form of the speaker cone pulsating back and forth, driven by the speaker’s electromagnetic motor. The force of that pulse helps determine volume. Remember from physics class, Force = Mass X Acceleration (F=MA). Therefore a more massive cone will create more force than a less massive one. This is one challenge for small speakers.
The other natural law that needs to be factored in is that lower frequency sounds have longer wavelengths and are generated more easily with larger speakers (that’s why subwoofers and woofers are larger than tweeters).
Along with the driver and cone, the speaker enclosure will significantly impact how a speaker sounds. It determines how much air is available for creating soundwaves and how those waves will emanate out toward the listener.
The Shrinking Process
When you work with a speaker manufacturer to create a miniature sound system you should not be starting from scratch. That will prove both too costly and slow for most industries. A smarter approach is an iterative process based on adjustments that can be made to existing products.
You will save time (and probably money too) if you partner with a manufacturer that already has a large catalog of products to work from. For example, a company came to MISCO looking for a miniature system that would include full range speakers that had to be less than 2” tall. Since MISCO has more than 70 years of experience manufacturing speakers and thousands of prototypes and finished products in its catalog, our engineers were able to start with an existing full range design that was only 1.5” and pair two of them with a compatible subwoofer as a starting point for the full system.
Having a potential solution already in existence is only half the battle though. Most people have a unique audio need in mind when they’re working with an OEM of loudspeakers. To improve performance or shrink components further on an existing speaker requires design, production, and testing tools that are state of the art.
The original full range speakers in the example above needed to be louder and better with low frequencies based on what the customer was looking for. The iterative process led MISCO engineers to focus on making adjustments to the enclosures first. One way to get more sound and lower the frequency response of an enclosure is by adding a passive radiator (however, that requires extra space and that wasn’t an option).
Another option is with a ported enclosure. A port can amplify a speaker’s energy and direct it toward the listener. The catch is that if you force the air through that tube too fast it will create a whistle or chuffing. This is obviously bad for audio quality. The way MISCO worked around this was by adding a second, internal port to the enclosure. Creating this unique technology enclosure required CAD software to design and 3D printing to prototype.
To confirm a miniature system matches the necessary specifications requires precise testing tools as well. The best in the world for this is the Klippel Near Field Scanner. This technology allows engineers to complete a 3D map of the sound radiation pattern for a speaker in a matter of hours (a task that took weeks or even months to do in the past).
How DSP Allows for More Shrinkage
One critical tool required to get great sound from small systems is digital signal processing (DSP). Think of it as packing an entire audio mixing studio into an amplifier board that can be hidden inside a speaker’s enclosure. The DSP allows an engineer to adjust how a system handles individual frequencies, add gain, change when the crossover from one speaker to another occurs, fine-tune timing, and more.
When MISCO works with a customer, we share with them the DSP settings inside their system, plus give them access to change those settings if they decide they want it to perform differently in the future.
Big Things Come in Small Packages
Smaller, better speakers is the goal in many industries. Achieving this requires people who understand the current limitations and have the knowledge and tools to push them further. Even if you only know what the limiting space factors are for the system you need (height, width, depth), please reach out to us and we’d be happy to answer any questions you may have. We work closely with many clients who need to protect their intellectual properties and trade secrets so discretion is never an issue.
