To reproduce the lowest audible frequencies, subwoofers are a specialised kind of speaker. They should be chosen based on the room’s features and your preferences. Choosing a subwoofer for your surround sound system might be confusing.
With Built-in Power
Self-powered ones are the most prevalent since they have an amplifier built right in. Powered ones often come with their volume (gain) and other settings that are independent of the receiver.
Connecting an amplified powered speaker to the Sub output on a receiver eliminates the need for an additional amplifier. This setup frees the amp/receiver from driving the mids and tweeters by removing the audio power burden.
Operating in the background or passively
Passive ones get their power from an external amplifier, much like other speakers in your system. Use an additional amplifier between the passive one and the home theatre receiver’s woofer preamp outputs if you want to use a passive one in your home theatre. The receiver no longer has to provide its amplifier power as a result of this setup.
To recreate low-frequency sounds, low-frequency bass output requires higher power. The passive one is connected to the receiver’s speaker terminals rather than a separate amplifier. If this is the case, the receiver must provide enough power to it to maintain bass effects. It is determined by the passive one’s power needs, the room’s size, and your personal preference for bass.
With up-and down-firing cones
With a front-firing (also known as a side-firing) speaker, the sound emanates from the front or side of the speaker enclosure. In the ones with down-firing drivers, sound travels from the driver to the floor.
Both methods provide comparable outcomes. Because these devices generate non-directional deep-bass frequencies, our ears have difficulty discerning where the sound is coming from.
When picking up or putting down a down-firing device, be careful not to puncture the exposed driver.
Passive Radiators, Ports, and the Like
More air is forced out of some specific model enclosures, improving bass response better than sealed enclosures. Additionally, passive radiators are used instead of ports in specific enclosures to improve efficiency and precision.
A flat diaphragm or a speaker without a voice coil may serve as a passive radiator. An active driver pushes air through a passive radiator, which responds to the vibrations created by the audio input. Its low-frequency response may be improved by using a passive radiator with an active driver.
To transmit all frequencies below a certain decibel level to it, a crossover is used. The primary, middle, and surround speakers receive all frequencies above that point. The crossover frequency is typically 100 Hz.
You can put it wherever in your room since the low frequencies it reproduces are non-directional. Various factors influence where furniture should be placed in a given space, such as room size, type of flooring, furniture composition, and kind of wall structure.
It works best near the front of the room, either to the left or right of the primary speakers or in the space’s extreme front corner.
Two outputs are standard on home theatre receivers, allowing you to connect as many as four devices at once.
Is it better to use a wired or wireless connection?
Wireless connection is becoming more common on powered ones. The lack of a lengthy cord between it and the receiver is made possible by the wireless capabilities.
The transmitter kit that comes with a wireless-enabled device may be connected to the outputs of any home theatre receiver.
The wireless one receives audio signals at low frequencies from the transmitter attached to the home theatre receiver. The subwoofer’s wireless receiver powers the amplifier, which drives the speaker driver and generates the necessary low-frequency sound.