Speakers head and horn, impedance matching, and connection

Will consider a lot of people from the power amp head (here mainly refers to the level) and the matching problem of the horn, actually matching is mainly the impedance matching of the two, which is why speakers first followed by the speaker output is written down all resistance (ohms), rather than power.

A what is the speaker impedance, if decide?

To determine this problem, first of all, review the high school physics, the concept of parallel and series, we all know the two resistors in series, the total resistance is equal to the sum of both, and the two parallel, the resistance is reduced, the total resistance is equal to two

Series: R = R1 + R2 +...

Parallel: 1 / R = 1 + 1 / R2 / R1 +...

Guitar speakers are usually used 4, 8, 16 ohms

Then according to the formula, we can know that two 8 ohm speaker series, the total impedance is 16 ohms. And in parallel, is 4 ohm.

Here are three common CAB model, respectively is 212 series, 212 parallel, 212 series parallel.

Second, how to connect?

The standard way, of course, is the output impedance, and speaker impedance match exactly, that is to say the speaker level after the output impedance of transferred to the total impedance of the speaker of the same value, then the connection. Such as 8 ohm match 8 ohms.

You can also use other 8 ohm output impedance to match is bigger than its speaker impedance, such as 8 ohm matching 16 ohms horn, or 4 ohms to match the horn 16 ohms. In so doing, makes the tone become dim, smooth, but it's better responsivity, the output will be a little bit.

Please note that don't use high low output impedance to match the speaker impedance, such as 8 ohm output impedance will not be able to answer the 4 ohm speaker. It will damage your speakers.

Here, we will review the ohm's law:

Flows through the current resistance in the circuit, and voltage is proportional to the resistance at both ends and is inversely proportional to the resistance of the resistance. This is ohm's law.

U = I x R (voltage = x resistance electric rate)

And the power calculation formula

P = U x I (x = power voltage current)

When after a fixed voltage level output to the speaker, if the impedance of the speaker is too small, then through the current is too large, so large power. So that is can get more volume, but please note that the maximum output power of the speakers are fixed, when the speaker power requirements is more than the power of the speaker can provide, so I couldn't move horn speaker is, in the long run speakers long overworked, certainly had to drop with fatigue. This is why can't use high output impedance to match low impedance of the speaker.

Why can't we say speakers 0 work load, the same is true, when the speaker impedance is 0, so short circuit connection, such as what are the consequences this needless to say, isn't it?

And if the speaker impedance is greater than the speaker output level, the current will become smaller, power is smaller, so will not beyond the scope of power of the speakers, equal to a man who can lift 100 catties, now let him for 50 kg weight, more natural, responsivity will better. This is known as the low efficiency of the horn. This concept is A bit like A CLASS A speaker's notion, often the speaker is not A great power, and it is very cost the life of the pipe, which we use A lot of effort, is the essence in order to get A little bit.

So if you want to more loudly, choose low impedance of the speaker, and if you respond better to details, choose high impedance of the speaker. For example, if your speaker output impedance is 8 ohms, then you choose 8 ohm speakers, will be the most full of big volume, very has the POWER of POWER. And choose 16 ohm speaker, the volume is small, but it will have a better reflect degrees, better details.