[Sticky] Live Sound & Proformance
If you’ve ever handled live sound, you know the recipe for creating quality live sound requires many steps. Your list of ingredients, shall we say, requires an understanding of sound and how it behaves, the know-how to effectively use a sound system), and the knowledge to choose and use your gear well. Add a dash of miking ability, stir in a pinch of thinking on your feet for when your system starts to hum or the vocals start to feed back, and mix.
In practice, there really is no "recipe" for creating a quality performance. Instead, musicians and engineers who effectively use sound systems have a wealth of knowledge that informs their every move before and during a live performance.
Components of a Live Sound System
Your band has worked hard to write and arrange your music. Your PA system should deliver that final product to your audience with clarity. Now whatever you end up buying probably isn’t going to offer the same clarity as the sound system at a big arena concert, but it’s very possible to find something that works for your band and your venues that sets your band apart from the competition all without breaking the bank. The best live music gear doesn’t necessarily have to cost thousands upon thousands of dollars.
A Public Address (PA) system is used to amplify sound electronically so that an audience can hear instruments, electronics and vocals clearly from a distance and over other ambient noises. A good PA system must have power amplification to drive speakers, mixing capability to set levels, equalizer to control frequency output, output control to send different signals at different levels to monitors or main speakers, and the ability to convert acoustic sound to electronic signal. These tasks can be handled in all-in-one units or by separate units that specialize in that task and offer more sophisticated controls. Here are some of the different components.
- Power Amplifier – This device uses electricity to amplify a low-power electronic audio signal to a level that is strong enough to drive (or power) loudspeakers. Power Amps come in various “wattages” that very depending on the “ohms” of a speaker. Wattage output on an amp lets you know how much amplification the power amp is capable of putting out. Ohms refer to the level of resistance to the power the speaker will have. The lower the Ohm, the greater the wattage. It is important to know what the Ohms level on your speaker is going to be before you select your amplifier.
- Loudspeakers – These refer to the component of the PA system with which we are all most familiar. The loudspeakers are the actual objects making the sound on a PA system. They are the result of the mix, the EQ (equalization), and amplification. Loudspeakers can be passive (they require a powered signal coming from an amplifier or a powered mixer) or active (they have their own plugs and require their own outlets).
- Monitors – These are typically smaller loudspeakers that are aimed at the performers and away from the audience that allow members of the band to clearly hear themselves and each other.
- Mixer – This component allows for multiple inputs or instruments to connect to a PA system. The mixer gives you the ability to control the volume of each input. Most mixers also give you the ability to control the output level on your main loudspeakers and your monitors independently of one another. While a standard mixer provides no amplification, some “powered mixers” come with a power amplifier built-in. Most mixers provide a basic EQ capability per each input and some also provide basic EQ capabilities for the entire mix.
- Equalizer – This component allows you to control at a very precise level the volume of each frequency group. While this may seem a bit unnecessary, feedback (that high screeching or low humming sound we’ve all heard come from a PA system) is typically an EQ issue and not a volume problem. Each room responds differently to different frequencies, and the ability to lower those hot frequencies may save you from an embarrassing feedback moment.
This basically covers the main components for the best stage equipment. Obviously you’ll need your inputs as well. The most common input in a PA system is a microphone, but some instruments can also be plugged directly into a PA system, such as electric guitars and keyboards.
There are some things you’re going to want to consider before you start shopping so that you can avoid wasting your time on systems that won’t be perfect for your band.
- Are you going to be controlling your PA yourself, or will you have someone to “man the board” at your performances?
- How big is your typical venue?
- How loud is your band? How many instruments or voices are you going to be running through the mixer at each performance?
- Will this also be your rehearsal PA? Are you going to be setting it up and tearing it down very often?
- How long are your performances? How much time can you justify setting up and tearing down your system?
- How far apart does your band stands? Do you have a need for wireless mics?
- How loud is your band? Do you have trouble hearing yourselves and will you require monitors?
- How important to you is not having cables running all over the place
There's a light at each end of this tunnel,
You shout 'cause you're just as far in as you'll ever be out