Studio engineering and live sound have similarities and differences. They both have their downs and ups, and although they may appear to be the same, there is still a world of difference that exists between them. One is essentially manufactured. That is, it is designed to be as attractive as can be achieved, and there is a little bit of concern for realism.
The other is about gaining the experience of something at the moment by reacting to real circumstances.
Therefore, if you are a novice that needs to know all there is about live sounds, this article is a practical guide to the basics.
A Practical Beginner’s Guide To The Basics of Live Sound
Having a sound understanding of signal flow is one of the most essential skills you can have as a live sound engineer. Without that, there is equally no music.
There is a need for you to know the source of the signal, as well as its destination, coupled with how to always get to its destination. Moreover, so as to achieve that, it is crucial that you know how every piece of the PA system works hand-in-hand.
Your home base can be said to be this mixer. It is the location where all your inputs are monitored, processed, and routed to the right outputs. Those inputs include microphones, FX, and instruments. All consoles are different, but everyone serves the same function.
Many consoles have about 8-32 channels, small subgroups, stereo “major” outputs, and several “aux” outputs serving the purpose of stage monitors and outboard effects.
Typically, analog consoles are outfitted with the inclusion of semi-parametric EQs on all channels. Likewise, outboard processors are usually used for dynamics and enable processing (comps, delays, gates, reverbs, etc.).
On the other hand, however, a lot of modern digital consoles feature completely parametric EQ gates, including compressors on all channels, with various effects processors. Taking a live sound engineering online course is also a great way to get the insight about sound mixing.
Signal processing is usually followed by all channels being ultimately routed to the primary stereo outputs and then sent to the PA system for the multitude to enjoy. Nevertheless, you should first connect the console to the speakers.
Graphic Equalizers are generally used to correct the kind of frequency response of a speaker. All you have to do is to connect the major outputs of your console to a graphic equalizer (GEQ) and use it to have the room tuned or correct problems in frequencies that may have been caused by standing waves present in the room.
Additionally, connect all your aux outputs to a GEQ before you send a signal to the stage and then make use of it to have the monitors “ringed out” or remove those frequencies which have the probability of causing feedback.
These are devices that divide your signal into two places: Frequencies that are low go to the subs, while everything else goes to the majors.
You could plug the major outputs of your console into the GEQ and then into the crossover inputs. Set the desired frequency at which the outputs that appear low will be corrected to the power amps for the subs. The high outputs should also be corrected to the power amps for those majors.
Some crossovers have a 3-way division for low, mid, and high speakers. However, they are for more developed systems only generally found in places where they were installed professionally.
Note that active speakers have crossovers that are built-in. Hence, you do not need an outboard unit.
Power amps have one responsibility: To supply power to passive speakers. There is absolutely nothing unique about them, as the sole control is volume output. Numerous engineers often decide to run their power amps at full blast, though if it is not correctly gain-staged, it could result in a low ratio of signal to noise.
Power amps are essential to your PA system. Moreover, when you use the wrong power amps, it could either lead to your speakers blowing up or the app catching fire. Interestingly, both could occur.
To accurately pair speakers and power amps, it is expected that you have the knowledge of the following:
- Power Amp Power
- Speaker Power
- Power Amp Impedance
- Speaker Impedance
The rest are a measure of resistance which informs on how resistant the speakers and power amps are to electricity. However, the most vital thing is that both the power amps and the speakers have similar ohm ratings.
Power is generally measured in watts and is frequently known as program, continuous, or RMS power rating. Therefore, you should use an amp that is about 50% more powerful than your speakers.
After successfully connecting your crossover outputs to the power amps, you could complete the chain by connecting the power amps and the speakers.
The speakers mark the end of the signal chain, that is, the last juncture before this whole electricity becomes music again.
Speakers are typically present in two main types: active and passive.
Active speakers are usually powered. There is a power amp developed into the unit, and everything you are required to do is plug the IEC cable into the wall in order to turn them on. They are more popular in smaller and more portable systems.
In order to achieve connecting active speakers to your console, you only need to run an XLR or TRS cable from the primary outputs on the console to the inputs on the speakers.
Passive speakers, on the flip side, are not powered. You need to purchase and connect an external power amp to have them turned on. They are usually more peculiar to larger permanent installations.
To connect passive speakers to your console, run an XLR from the major outputs of your console to the inputs on the power amps. After that, connect the outputs of the power amps to that of the inputs of the speakers with the use of TS or Speakon cables.
Always bear in mind that every speaker should be paired with a graphic equalizer and a well-matched power amp.
The descriptions that have been made in this article are perfect as a starting point or a reference guide when you are setting up in readiness for live sounds. You can then be rest assured to receive numerous gigs. And it will be time for load-in, soundcheck, and show time!