Exploring Common DIY Terminology (work in progress)

Preface

I started this article with the intention of offering a guide to DIYers, mostly those new to the field, that defines and explains the terminology you often see in discussions on the topic of DIY loudspeakers. Now, I have plenty of learning to do myself, and am under no illusion that what I do know is complete and correct. Because of this, I want these articles to be living documents. By that I mean, I'd like the DIY community to offer input on each definition to expand and clarify...

Baffle

A structure that surrounds and supports loudspeaker drivers, providing a surface from which sound radiates into a listening space. Some may discount the baffle as simply being the front of the speaker upon which drivers are mounted, however its purpose is varied and it can significantly impact the overall performance of a loudspeaker:

• First, the baffle should be as rigid as possible to provide mechanical support for each driver installed and minimize unwanted vibrations or

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Baffle Step Compensation (BSC)

Baffle step compensation, sometimes known as baffle step correction, is a technique used in loudspeaker design to address the acoustic effects caused by the transition between the free space in front of the speaker and the restricted space around the speaker, typically due to the loudspeaker's physical enclosure or baffle. When sound waves emanate from a loudspeaker, they spread out in all directions. However, when the loudspeaker is placed on a baffle,...

Cabinet Resonances

Cabinet resonances refer to the unwanted vibrations and resonant modes that occur within the enclosure or cabinet of a loudspeaker. These resonances can negatively impact the overall sound quality by introducing coloration, distortion, and uneven frequency response. Cabinet resonances can arise from various factors, including the materials used, the cabinet's construction, and the internal air volume. To reduce cabinet resonances, loudspeaker designers employ several...

Enclosure

The design of the loudspeaker enclosure is crucial in achieving optimal sound quality and performance. The enclosure serves multiple purposes, including providing structural integrity, controlling resonance, and managing the interaction between the drivers and the surrounding environment. A well-designed enclosure can significantly impact the frequency response, transient response, and overall clarity of the loudspeaker system. There are several types of loudspeaker enclosures,...

Passive Radiator

A passive radiator, often shortened to simply 'PR', is a component used in loudspeaker and subwoofer design to enhance bass performance. It is a type of driver without a voice coil and magnet structure but has a diaphragm and suspension that moves in response to changes in air pressure inside the enclosure. A passive radiator is located within the same volume as the driver it is supplementing, but could be placed on any side of the cabinet. When the active driver moves...

Midrange

A midrange driver is a loudspeaker driver designed to reproduce midrange frequencies in an audio system. It is responsible for bridging the gap of frequencies between the bass and treble ranges, typically from around 300 Hz to 2000 Hz, depending on the specific design, tweeter and woofer choice, and crossover points.

Design criteria for midrange drivers:

• Frequency Range: Midrange drivers are designed to cover the midrange frequency band with clarity and accuracy.

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Resonance

Resonance refers to a phenomenon where an object or system vibrates with a significantly increased amplitude at a specific frequency when exposed to an external force or energy. This frequency at which the object or system vibrates most strongly is known as the resonant frequency. In loudspeakers, resonances can occur in various components and aspects of the system:

• Diaphragm Resonance: The diaphragm of a loudspeaker driver (cone or dome) can have natural resonances due

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Flux Modulation

Flux modulation, also known as magnetic flux modulation or magnetic field modulation, is a technique used in loudspeaker design to control and manipulate the magnetic field strength within a driver's magnetic circuit. It involves intentionally varying the magnetic flux density in a controlled manner to achieve specific performance characteristics and improve the overall sound quality. The process of flux modulation typically involves the application of an additional...

Le (Thiele/Small Parameter)

Le refers to the voice coil inductance of a loudspeaker driver. It is an electrical property that plays a significant role in the driver's performance and behavior. The voice coil is a wire wound around a hollow cylinder called the former and is attached to the loudspeaker's diaphragm or cone. When an audio signal is passed through the voice coil, it interacts with the magnetic field generated by the permanent magnet or electromagnet surrounding the voice...