Harman Kardon AVR 254 Service Manual Download Page 15

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There are different types of audio and video connections used to
connect the receiver to the speakers and video display, and to connect
the source devices to the receiver. To make it easier to keep them all
straight, the Consumer Electronics Association (CEA

) has established

a color-coding standard. See Table 1.

Table 1 – Connection Color Guide

Types of Connections

This section will briefly review different types of cables and connections.

Speaker Connections

Speaker cables carry an amplified signal from the receiver’s speaker
terminals to each loudspeaker. Speaker cables contain two wire conduc-
tors, or leads, inside plastic insulation. The two conductors are usually
differentiated in some way, by using different colors, or stripes, or by
adding a ridge to the insulation. Sometimes the wires are different,
colors e.g. copper-colored and silver.

The differentiation is important because each speaker must be connected
to the receiver’s speaker-output terminals using two wires, one positive
(+) and one negative (–), referred to as speaker polarity. It’s important
to maintain the proper polarity for all speakers in the system, or perform-
ance can suffer, especially for the low frequencies.

Always connect the positive terminal on the loudspeaker, which is usually
colored red, to the positive terminal on the receiver, which is colored as
shown in the Connection Color Guide (Table 1). Similarly, always connect
the black negative terminal on the speaker to the black negative terminal
on the receiver.

The AVR 254 uses binding-post speaker
terminals that can accept banana plugs
or bare-wire cables. Banana plugs are
simply plugged into the hole in the middle
of the terminal cap. See Figure 1.

Figure 1 – Binding-Post Speaker Terminals With Banana Plugs

Bare wire cables are installed as follows (see Figure 2):

1. Unscrew the terminal cap until the pass-through hole in the collar is

revealed.

2. Insert the bare end of the wire into the hole.

3. Hand-tighten the cap until the wire is held snugly.

Figure 2 – Binding-Post Speaker Terminals With Bare Wires

Subwoofer

The subwoofer is a specialized type of loudspeaker used to play only
the low frequencies (bass), which require much more power than the
other speaker channels. In order to obtain the best results, most speaker
manufacturers offer powered subwoofers, in which the speaker contains
its own amplifier on board. Usually, a line-level (nonamplified) connection
is made from the receiver’s Subwoofer Output to a corresponding jack
on the subwoofer, as shown in Figure 3, but sometimes the subwoofer
is connected to the receiver using the front left and right speaker outputs,
as with passive in-wall subwoofers, and then the front left and right
speakers are connected to terminals on the subwoofer.

Although the subwoofer output looks similar to the analog audio jacks
used for the various components, it is filtered and only allows the low
frequencies to pass. Don’t connect this output to any other devices.
Although doing so won’t cause any harm, performance will suffer.

Figure 3 – Subwoofer

Connecting Source Devices to the AVR

The AVR 254 is designed to process audio and video input signals,
playing back the audio and displaying the video on a television or
monitor connected to the AVR. These signals originate in what are
known as “source devices,” including your DVD player, CD player, DVR
(digital video recorder) or other recorder, tape deck, game console,
cable or satellite television box or MP3 player. Although the tuner is
built into the AVR, it also counts as a source, even though no external
connections are needed, other than the FM and AM antennas and the
XM antenna module.

Separate connections are required for the audio and video portions of
the signal, except for digital HDMI connections. The types of connections
used depend upon what’s available on the source device, and for video
signals, the capabilities of your video display.

ubwoofer

Preout

Audio Connections

Left

Right

Front

(FL/FR)

Center

(C)

Surround

(SL/SR)

Surround Back