When shopping for speakers online, you may have come across the term 3-way design. What are they and how do they differ from conventional speakers? Here, we take a closer look at 3-way speakers and the advantages they offer in home theatre systems.
A three-way audio speaker produces sound from three separate drivers or transducers. The three speakers i.e the woofer, mid-range and tweeter are optimized to deliver the greatest efficiency in their respective range of frequencies. In technical specifications or drawings, they may be denoted as LF (low frequency), MF (mid frequency), and HF (high frequency).
As the speaker drivers are optimized to work in a set frequency range, together they deliver clearer, more accurate sound along with reduced amplification requirements. To put things in perspective, most portable Bluetooth speakers usually have a coaxial or a full-range driver while many bookshelf speakers are 2-way and use only two drivers i.e. a mid-bass and tweeter driver.
How are 3-way speakers designed?
To optimize the speaker’s sound, an assemblage of electronic circuits called crossovers are integrated into the design. The crossover feeds each driver with a filtered frequency range of the audio signal from the amplifier or AV receiver. The crossover circuit feeds the woofer, midrange, and tweeter driver with only the low, mid and high-frequency signals respectively. This electronic wizardry is what ultimately forms the basis for a three-way speaker. In home theatre speakers, the crossover is usually placed inside the cabinet.
In professional audio, however, rack-mounted active electronic crossovers are used to distribute the frequency in either 2-way, 3-way or even 4-way configurations. The same principle is used in bi-amping or tri-amping. However, the amplification process happens after the frequencies are segregated via a crossover.
A look at the speaker drivers
So, do the three drivers differ in size and performance? Yes, they do. Let’s have a look at what sets them apart.
Woofer or Low-Frequency Driver
The woofer is the largest driver in the speaker, usually measuring between 5 to 12 inches in diameter. It generates low-frequency sounds in the bass range, such as drums, bass guitars, explosions and thunder etc. Most woofers have a cone either made of paper or plastic, a strong permanent magnet and a wire roll known as the voice coil. The same components are are used for the other transducer as well. However, they differ is terms of size, voice coil and cone material selection. From all the three driver variants, the woofer emanates the strongest sound thereby requiring relatively high amounts of power.
Mid-Range or Mid-Frequency Driver
In comparison to LF drivers, the mid-range driver is typically smaller ranging between 6 to 8 inches in diameter. It takes up the task reproducing mid-frequencies in which sonic elements like vocals, speech, and most musical instruments are nested comfortably. When heard in isolation, it will produce a reasonable sound. However, it will lack bass punch and treble brightness. Given how important the mid-frequencies are for the listening experience, many speakers often deploy more than one mid-range driver for added power, clarity and definition.
Tweeter or HF Driver
The tweeter is the smallest driver in the speaker. It usually measures no more than a few inches across. The drivers are typically made from highly conductive metals such as aluminium, titanium, magnesium, or even copper. It operates at the treble end of the audio spectrum, producing high-frequency sounds such as hi-hats, cymbals, percussions, flutes and others. Without a tweeter, the sound emanating from a speaker will lack brightness, clarity, and deliver a dull, muted and lacklustre sound.
The takeaway
Three-way speakers are preferred by audiophiles because of the clarity, tone and efficiency they deliver. Typically, most floorstanding speakers are 3-way design. However, there are 3-way bookshelf speakers available especially from high-end, audiophile-grade brands. If budget is not a constraint, we would definitely suggest buying a 3-way speaker for your home theatre system in India.