Types of Tweeters and their Functions
Tweeters are small audio drivers designed specifically to reproduce high frequencies. Tweeters are small in size since they reproduce smaller sound waves than regular speaker drivers. They are mostly limited to a range of between 3 KHz to 20 KHz. Let’s take a look at different types of tweeters and their functions.
Dome tweeters: These are the most common type of tweeters.They come in different driver materials - the most common being titanium,plastic,aluminum,beryllium, doped fabric, treated cloth, silk and composite materials.
There are two classifications of dome tweeters based on which of the above materials is used to construct them, Soft-dome tweeters and metal dome tweeters.
Soft-dome tweeters have lower resonance frequency, more headroom for extreme sound pressure and higher power handling. They are however very delicate and less stiff.
There isn’t a single perfect material for a dome tweeter, so the main thing would be to balance all the essential factors, without compromising on any important aspect during the design process. Dome tweeters are mostly used in home audio equipment.
Cone Tweeters: These types of tweeters deliver crisp highs and are inexpensive to design and manufacture, however they are prone to moisture damage.
Piezo Tweeters: They are highly effective as they are capable of delivering loud highs with minimal power input, which makes them ideal for use in less powerful speaker systems and portable radios.
Ribbon Tweeters: Ribbon tweeters use a thin, flat diaphragm. The diaphragm is generally made of an aluminum foil or metalized polymer film. These tweeters are expensive and are less effective in producing the high-mids of a track.
Super Tweeters: A super tweeter is a special type of tweeters that are designed to extend the high-frequency response of normal tweeters in a coaxial speaker. They reproduce the highest frequencies that regular tweeters cannot. They enhance the density and detail of an existing sound system. They’re ideal for reproducing highs from high-fidelity systems such as ultrahigh definition Bluray.
Ring Radiator/Concentric Tweeters: Ring radiator tweeters, also known as concentric tweeters, have a center plug surrounded with some rings. They produce accurate and detailed highs. Moreover, they disperse high frequencies widely. However, they’re less common.
Air Motion Transformer Tweeters: Air motion transformer (ATM) tweeters are a less common type of tweeters. They’re made of aluminum conductors and a thin, folded film diaphragm. The diaphragm is positioned between opposing magnets. As current passes through, the diaphragm folds. It contracts and expands as it folds, thereby forcing air in and out. As a result, high-frequency sounds are produced. However, ATM tweeters are expensive and challenging to manufacture.
Plasma/Ion Tweeters: The operating principle behind this tweeters is the use of electrically charged ionized gas. Plasma/ion tweeters are extremely complex than other types of tweeters. Their moving mass is exceptionally low, thereby making them highly responsive with minimal current input. However, they’re less safe for use because they produce small amounts of ozone, which is a poisonous gas.
Horn Tweeters: Horn tweeters are any of the aforementioned tweeters mounted in a horn structure. Thus, the design behind a horn tweeter can be a dome driver, piezo driver, cone driver, or any other tweeter driver mounted in a horn. The horn structure enhances the efficiency of the direction of high-frequency sounds. Horn tweeters are challenging to design but are very efficient. These tweeters are most ideal for use in outdoor speaker systems due to their loudness and wide sound dispersion.
In Conclusion, tweeters come in different shapes, sizes, materials, and operating principles. Although they’re all designed to reproduce highs, some are more reliable in certain applications than others. Now that you know the different types of tweeters, you’ll be able to figure out the ideal type for a specific application.