How To Connect a Subwoofer To a Receiver Without Subwoofer Output?

One of the key elements of a multichannel sound system is the subwoofer. It is obligatory for home theater configurations. However, there are difficulties in connecting such an important element of an audio system due to the huge variability of amplifier models and configurations.
We will try to reveal the topic of standard and non-standard connection of subwoofers.

What is a subwoofer?

A subwoofer is a speaker designed to reproduce the low frequencies that are at the lowest sensitivity of the human ear. The term “Subwoofer” is used to describe a woofer system in a separate enclosure. The standard connection method is very simple. A special SUB OUT of an amplifier or receiver is connected to the SUB In of a subwoofer.

The source devise or subwoofer without SUB OUT

Frequent cases when a source device has not specialized out for subwoofer. There are two solutions for connecting a subwoofer:

To connect a subwoofer to an av receiver without sub out, you can use the output terminals that are used to connect speakers. In this case, the subwoofer and speakers will work in the low-frequency range in parallel.

The subwoofer is sometimes connected to the output terminals located on the amplifier, while the loudspeakers are connected to the high-level output terminals located on the subwoofer.

There may be a third option if the subwoofer is passive. If the subwoofer has two terminals in the back, then the subwoofer is connected to the Pre Out through the amplifier.
Very often, passive subwoofers are connected in parallel to the front speakers:

There are three terminals on the rear panel of the subwoofer – there are “pluses” from the front speakers and their common “minus” (minuses twist together)

There are four terminals on the back of the subwoofer – these are the “pluses” and “minuses” of the front speakers.