Connecting Speakers with Trans- formers

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3.Connect the two pairs of speakers in parallel. If you connected 8 ohm speak-

ers the total impedance of both pairs is 8 ohms (16 ⎟ 2 = 8).

Note: If each of the four speakers is 8 ohms, the total speaker impedance of the combined series/parallel connection described above is also 8 ohms. Like- wise, the total speaker impedance is 4 or 16 ohms if the speakers are 4 or 16 ohms, respectively.

4.Connect the speakers’ negative (–) ter- minals to the COM terminal on the back of the amplifier.

5.Connect the speaker’s positive (+) ter- minals to the speaker terminal (4Ω, 8Ω, or 16Ω) on the back of the amplifier that matches the total speaker impedance as calculated in Step 3.

Connecting Speakers with Trans- formers

For the best results when you connect two or more speakers to your system, use a line transformer (not supplied) for each speaker.

Transformers offer these advantages:

•You can connect speakers with different impedances without causing differ- ences in output between the speakers.

•You can add or remove a speaker from the system without having to recalculate the entire system’s impedance.

•You can reduce signal loss when you use speaker wire over 50 feet long.

Line transformers have several connectors called taps.

Taps

The primary taps (on one side of the trans- former) are the inputs and are rated in watts. The secondary taps (on the opposite side of the transformer) are the outputs and are rat- ed in ohms.

Primary	Secondary
Taps	Taps

Cautions:

•Before you connect the speakers, be sure the total wattage of the primary tap you intend to use does not exceed the amplifier’s maximum 100-watt output power rating.

•Avoid multiple connections to the 70V RMS and COM terminals on the back of the amplifier.

Connections			11

MPA-125 specifications

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