| One word to remember before reading
any further: Ohms! Ohms together with "+" and "-" is what we need to be
aware of when connecting speakers. If you don't have your Ohms right, then
you might end up with a burned up amplifier.
Every speaker has ohms. The term is Nominal
Impedance and the unit is ohms. If you don't know the nominal impedance of
your speaker, look for something called Re. Re is the resistance of the
voice coil, and is close in value to the nominal impedance. Another thing to
remember is SERIES and PARALLEL.
Series connection means we simply add each
driver's impedance for a total impedance. This is described as
Rtot = R1 + R2+......
1/Rtot=1/R1+1/R2+........
So, how does one connect in series or parallel?
Well, I will try to explain by using examples and figures.
| Example 1 - Series connection of two
4 ohms speakers. Let's say we have two subwoofers that have a
nominal impedance of 4 ohms each. For a series connection, the total
impedance would be 4 + 4 ohms = 8 ohms. The connection is done as
shown in the figure below. |
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| This connection would
give a final impedance of 8 ohms. |
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| Example 2 -
Parallel connection of two 4 ohms speakers. For a parallel
connection we would get a total of 2 ohms. Mathematically speaking it
would be 1/Rtot = 1/4+1/4; 1/Rtot = 0.5 which means Rtot = 1/0.5=2. To
connect said woofers in parallel: |
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| This connection would
give a final impedance of 2 ohms. |
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Example 3 -
Series/Parallel connection of four 4 ohm speakers. Let's say
we have four woofers that each has a nominal impedance of 4 ohms.
For a series connection, we would get 4+4+4+4=16 ohms. Since most amps
can handle down to 4 ohms bridged, a series connection would be quite
a waste of amplifier power. In theory, you would get 4 times the power
going from 16 to 4 ohms. And since we learned before that parallel
connections achieve lower impedance, let's see what happens if we try
to hook the four speakers up in another way. |
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Two series of 8 ohms each that
are parallel connected will yield a 4 ohm total impedance.
Mathematically speaking:
1/Rtot = 1/8+1/8; 1/Rtot=0.125+0.125; Rtot=1/0.25 = 4 ohms
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