Mesa/Boogie 100, 45, 55 owner manual Speaker Impedance Matching & HOOK-UP Guide, Positive

SPEAKER IMPEDANCE MATCHING & HOOK-UP GUIDE: (Continued)

PARALLEL: When wiring in parallel, the resistance of the speakers decreases. Two 8 ohm speakers wired in ( hooked-up ) Parallel results in a 4 ohm load. It’s easy to calculate the effect of a resistive load when all the speakers are all the same resistance. It is really not suggested to wire different resistive load values in Parallel ( 8 and 4, 16 and 8 etc. ) The formula for figuring the total impedance in Parallel is the multiplication of the two loads divided by the sum of the two loads - i.e. putting two 8 ohm speakers in Parallel results in a 4 ohm load. Connect the Positive side of Speaker A to the Positive side of Speaker B - Connect the Negative side of Speaker A to the Negative side of Speaker B.

Speaker A

8 Ohms

Total Load = 4 Ohms

Speaker B

8 Ohms

NEGATIVE

POSITIVE

COMBINATION OF SERIES & PARALLEL: This is really just two sets of Parallel wired speakers connected in series. This is how

you maintain a consistent load with multiple speakers. The importance of this is more evident when you have more than one cabinet to
									connect to your amplifier. This is when
									you need to figure out the loads and how
SPEAKER A				SPEAKER B					to wire them up without applying too low
									of a resistance on the amplifier.
		S			S				Simply connect the Positive side of
						HA
	K	H		A	Made by		D		Speaker A to the Positive side of Speaker
C Electro-Voice
								O
A	Made by		D	C Electro-Voice
			O	L				W
L			W	B					C.
B
									Connect the Negative side of Speaker A
All 4 Spkrs.									to the Positive side of Speaker B, then
									on to the Positive side of Speaker D and
are 8 Ohms
									finally on to the Negative side of Speaker
SPEAKER C				SPEAKER D					C.
									And lastly, connect the Negative side of
		S				S			Speaker B to the Negative side of
	K	H
			D		K	H			Speaker D.
C Electro-								D
					Made by
A		Made by		A
			O		Electro-Voice
L			W	L
B
				B					4 Eight ( 8 ) Ohm speakers wired in Se-
									ries Parallel = a Total Load of 8 Ohms.

POSITIVE

NEGATIVE

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