So, you got yourself a great pair of Seismic Audio Dual 15″ Pro Audio PA / DJ Speakers. You also have great amplifier to power those speakers. You are ready to get out there and start rockin’ the house! There is just one problem – you don’t know how to hook the speakers to the power amp.
The most important place to start is at the amplifier itself. It is extremely important to make sure that amp is capable of handling the impedance (ohm) load from your speakers. For this blog, we are going to assume that you are using 1 channel of your amp and have a single pair of identical speakers and want to run in mono mode. Other configurations will be addressed in future blog entries. Most of the time, when running a PA in this mode, your speakers are going to be daisy chained (or run parallel). You daisy chain speakers by hooking one speaker up to an amplifier and then out of that speaker you hook up another speaker. Keeping in mind that for this example we have only 2 speakers with the same impedance rating, when you daisy chain speakers you divide the impedance. (For example, two 4-ohm speakers connected in parallel result in a 2-ohm overall impedance.) This is why it is important to be sure your amplifier is capable of handling the ohm load. If the ohm load of your speakers is lower than what your amplifier can handle, you will most likely cause severe damage to you amplifier! (And most of the time – void your warranty!)
Now, let’s go back to your pair of Seismic Audio Dual 15″ Pro Audio PA / DJ Speakers (SA-155T) for an example. Individually these speakers run at 4-ohms a piece. When you hook them up parallel (daisy chained), the ohm load of the speakers is 2-ohms. Remember, running your speakers parallel divides the impedance. A large majority of amplifiers can handle 2-ohms per channel (running non-bridged mode) – but it is important that you check your amplifier and find out! So, if your amp can handle 2-ohms per channel, you are ready to hook up the SA-115T because daisy chained together they carry a 2-ohm load.
Let’s say you got the same 2-ohm per channel amp, but you have a pair of speakers with a higher ohm load. So, you have two 8-ohm speakers and when you hook them up is parallel they would be a load of 4-ohms. Can you do this? Yes, as long as the ohm load is not lower than the amp is capable of handling then you are okay.
But what if you have an amp that is 4-ohms per channel and the SA-155Ts which run at 2-ohms parallel? Well, you guessed it – DO NOT DO IT! If you run this configuration, you will more than likely severally damage your amplifier!
This is just a general example and there are many ways to configure running your speakers to an amplifier. What I am trying to point out is the fact that you should NEVER run an ohm load lower than your amp is capable of handling. This can permanently destroy your amplifier!
Now that you have figured out that your amplifier can handle the ohm load of your speakers, you are ready to get them hooked up! The last step is actually connecting the speakers to the amplifier. You need to find out what kind of connectors your amplifier and your speakers use. Some might only offer binding post connectors in which you would use banana plugs. Others might have inputs for 1/4″ connectors or speakon connectors. What is the difference in these connectors? In the context of this blog entry, it is just the connector itself. When applicable, I prefer to use speakon connectors because they lock in place and you know that you have a great, secure connection. Also, when the stage is crowded, speakon connectors insure that no one is going to accidentally step on a cable and pull it out of the speaker. Another thing to keep in mind when buying a speaker cable, the heavier gauge wire you use, the better. Heavier gauge wire insure that you are getting less resistance from the wire and therefore, less signal loss. Keep in mind that the lower the gauge number of the wire, the heavier the wire, i.e. 14 gauge is heavier or thicker than 16 gauge. The size of the wire is really dependent upon the amount of power you are pushing through it and the distance of the run. The details of that are beyond the scope of this blog entry though. Just be sure to use speaker cables and not instrument cables!
Well, you got the correct amplifier, a great set of speakers, and all the proper cables. All that is left is to hook up the speakers and to power up the amplifier. To daisy chain the speakers just plug in a speaker cable into the output of the proper channel of the amp and run it one of your speakers. Once you have put that cable into the input of the speaker, grab another cable and go from that speaker to your other speaker. Now you are ready to start the gig and to bring down the house!