Page 155 - Electronic Mechanic - TP - Volume - 2

ELECTRONICS MECHANIC - CITS

Subwoofer Preamp Outputs

Another type of speaker that needs to be connected to a home theater receiver is a subwoofer. The subwoofer
doesn’t connect to the terminals provided for the other speakers. Instead, the subwoofer connects to an RCA-type
connection that is labeled as Subwoofer, Subwoofer Preamp, or LFE (Low-Frequency Effects) output.
This type of connection is used because subwoofers have built-in amplifiers, so the receiver doesn’t power the
subwoofer. It only supplies the audio signal. RCA-style audio cables are used for this connection.

Home theater receivers provide at least one subwoofer output. Still, many provide two, as shown in the above
example. This provides added setup flexibility.
Multichannel Analog Audio Inputs and Outputs

Higher-end home theater receivers offer an additional analog audio connection option, referred to as a multichannel
analog audio connection.

A separate connection for each channel of audio is provided. This means that just as there are left-channel and
right-channel analog audio connections for stereo, for surround sound, it is possible to include separate analog
audio connections for the center, left surround, right surround, and, in some cases, left surround back and right
surround back. The connections use RCA jacks and cables.
Multichannel Analog Outputs
The most common multichannel analog connection options, which are found mostly in mid- and high-end home
theater receivers, are multichannel analog audio outputs.
These outputs connect a home theater receiver to external amplifiers. However, when multichannel analog preamp
outputs are used, these outputs disable the home theater receiver’s internal amplifiers that are designated for the
corresponding channels. You can’t combine the power output of an internal amplifier with an external amplifier for
the same channel.

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CITS : E & H - Electronics Mechanic - Exercise 158 CITS : E & H - Electronics Mechanic - Exercise 158