To bridge an amp is to combine the power of two channels to drive one speaker. This will double a single channel power, for example, two 50 watt channels would merge into one 200 watt channel. It is the most desired power, and you can use it in your overall system. If you have two subs in your system and you want to drive each with a 100 watts of power you can do one of the following ways.
First to drive each speaker with its own stereo channel of 100 watts or you can wire both speakers to a bridged amp that creates 50 watts in stereo or 200 watts in mono.
If you choose the second way you’ll get the same power but with a less cost or lower dollar for the watts. But you must set speakers impedance in order to achieve this. If your amp is only 2 ohm stable, you’ll only gonna get a 4 ohm load, so you must either purchase two 8 ohm woofers and wire them in parallel or you can buy two 2 ohm woofers and wire them in series. That is why it is crucial to plan your system carefully before purchasing any equipment.
Bridging two channels of an amp will cut in half the effective impedance of the speaker load. An example, if you bridge an amp to a 4 ohm speaker will make the effective impedance 2 ohm. This is why when bridged, an amp can quadruple the power of a single channel. Each of the previous two channels will see a load of 2 ohms, and will give a stereo 100 watts output by two channels. And since there is one channel it combines both 100 watt channels and become a 200 watts channel. This is very important, many people actually believe if their amp is 2 ohm stable then they can bridge it to a 2 ohm speaker load. This isn’t the case as a bridged amp will see a 2 ohm speaker load as a 1 ohm.
