Determining Total Speaker Impedance

32-2001.fm Page 6 Friday, February 4, 2000 7:53 AM

3.Touch the positive end of a 1.5-volt flashlight battery to the speaker ter- minal that does not have the wire attached to it.

4.Touch the negative end of the bat- tery with the lose end of the wire attached to the other speaker termi- nal. Note the direction of the cone movement — inward or outward.

5.If the speaker cone moves outward, the speaker terminal where you touched the positive end of the bat- tery is positive. Mark that terminal with a + and mark the other terminal with a –.

If the speaker cone moves inward, the speaker terminal with the wire attached that touched the negative end of the battery is positive. Mark that terminal with a + and mark the other terminal with a –.

6.Remove the wire.

Repeat Steps 2–6 for each speaker with unmarked terminals you plan to connect to the amplifier.

Caution: A total speaker impedance that is higher than 16 ohms (Ω) or lower than 4 ohms can damage your amplifier or speakers. Be sure to make the proper connections.

Before you connect speakers to the am- plifier, you must determine the total speaker impedance. In determining the total speaker impedance, you must first determine if your speakers are connect-

ed in series, parallel, or series/parallel combined.

Note: We recommend that you use speakers that are rated the same (for example, all 8-ohm speakers) for all se- ries or parallel connections.

•Speakers are connected in series when the first speaker’s positive ter- minal is connected to the next speaker’s negative terminal. Deter- mine the total impedance of speak- ers connected in series by adding up the individual impedances of all the connected speakers.

For example, if you want to connect two 8-ohm speakers in series, add 8 (the impedance of one speaker) plus 8 (the impedance of the other speaker) for a total speaker imped- ance of 16 ohms.

•Speakers are connected in parallel when all their negative terminals are connected together and all their positive terminals are connected together. For speakers rated the same, find the total impedance of speakers connected in parallel by dividing the impedance of one speaker by the number of speakers.

For example, if you want to connect two 8-ohm speakers in parallel, divide 8 (the impedance of one speaker) by 2 (the number of speak- ers) for a total speaker impedance of 4 ohms.

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