Mesa/Boogie F-50, F-100 Speaker Impedance Matching & HOOK-UP Guide, Mis-Matching, Series

SPEAKER IMPEDANCE MATCHING & HOOK-UP GUIDE:

IMPEDANCE:

Wiring up speakers to provide the most effective load and making sure that all of them are in phase will help in creating the best sound possible. This is not too difficult, as long as you understand a few things about loading and how to connect your speakers to provide an optimal resistive load.

Mesa Boogie amplifiers can handle 4 and 8 ohms effectively. Never run below 4 ohms in a tube amplifier unless you are absolutely certain that the system can handle it properly; this can cause damage to the Output transformer. A few amplifiers can handle 2 ohms effectively without damaging them ( for example the Mesa’s Bass 400+ ). You can always have a higher resistance ( 16 ohms, for example ) without damaging results, but too low of a resistance will likely cause problems.

MIS-MATCHING:

When running a higher resistance ( for example: 8 ohm output into 16 ohm cabinet ), a slightly different feel and response will be eminent. A slight mismatch can provide a darker smoother tone with a little less output and attack. This response is a result of the amplifier running a bit cooler. Sometimes when using more than one cabinet a mismatch will be the only option.

WHAT IS MY CABINETS IMPEDANCE:

If you have only a single speaker, you just match that single speakers impedance to the amplifier, and you are done. In many cases, you will have a number of speakers, and then you must calculate the “load” that the amplifier will need to support. There are generally three ways to wire multiple speakers together. They are as follows:

SERIES:

When you wire ( hook-up ) speakers in Series, the speakers resistance ( as measured in ohms ) is additive - i.e. putting two 8 ohm speakers in Series results in a 16 ohm load.

POSITIVE =

NEGATIVE =

			S					S
								H
	K		H			K			A
				A
				D	C		Made by
A		Made by			A				O
				O
C									D
		Electro-Voice			L		Electro-Voice
L									W
				W
B					B

Speaker A = 8 Ohms Speaker B = 8 Ohms

SERIES: Connect the Negative side of Speaker A

to the Positive side of Speaker B

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