In a building or on an open dance floor, where thousands of visitors gathered near the podium, you can’t do even 30 watts with simple home speakers. To produce the proper effect of presence, you need high-power speakers of 100 watts and above. Let's figure out how to choose concert speakers.
High-power concert speakers are an acoustic kit that differs not only in speaker sizes. The total output power of each speaker reaches 1000 or more watts. When using speakers for outdoor concerts in the city, music will be heard for 2 km or more. Each column weighs more than a dozen kilograms - due to the use of the most massive magnets in the speakers.
Most often, these speakers do not have a built-in, but a remote amplifier and power supply, which classifies them as passive. The devices are protected from moisture and dust, which makes their use possible even in wet and windy weather.
Principle of operation
The acoustics of the concert-theater type works on the same principle as other speakers. Sound supplied from an external source (for example, from an electronic mixer or a sampler with a karaoke microphone) passes through cascades of amplifiers, gaining power hundreds of times greater than that produced by the primary sound source. Entering the separation filter included in front of the speakers and dividing into sound subbands (high, medium and low frequencies), the processed and amplified sound causes vibrations of the speaker diffusers with the same frequencies that were generated on electronic musical instruments and the performer's voice.
Most often, two- and three-way speakers are used. For cinemas where multichannel and surround sound is crucial, several bands are also used. The simplest stereo system is two speakers in which all three bands are transmitted in each of them. It is called 2.0. The first number is the number of speakers, the second is the number of subwoofers.
The most complicated 32.1 stereo system is 32 “satellites” reproducing high and medium frequencies, and one subwoofer is often used in movie theaters. It has an optical sound output connected to a movie projector or a large 3D monitor. Monosystems for concert performances and film screenings are almost never used anywhere, and in everyday life they are replaced by stereo systems (sound in the country, in the car, etc.).
Basically, the range of concert performance speakers is represented by the following manufacturers:
- Current Audio
- dB Technologies;
- ES Acoustic
- Fender pro
- Focal chorus;
- HK Audio;
- Topp Pro
- “Russia” (a domestic brand that collects acoustics for trading floors mainly from Chinese parts and assemblies) and a number of others.
Some manufacturers, focusing exclusively on legal entities and wealthy clients, produce 4-5 channel speakers. This overprices the kit (speakers, amplifier and power adapter).
When choosing, focus on large sizes, high power, because a column in the form of a small box is unlikely to produce a sound that allows you to create the effect of being on the dance floor or in the cinema. But do not overdo it with the mass of columns. If, for example, acoustics is chosen mainly for weddings and other celebrations organized, say, in country houses and cottages, then acoustics are suitable for a small stage up to 100 watts. If the celebration hall or restaurant has an area of 250-1000 square meters, enough power and 200-300 watts.
The trading floors of hypermarkets do not use a single powerful column that can stun a visitor with bright and inviting advertising. It connects up to several dozen small broadband built-in speakers or speakers with power up to 20 watts. What matters here is not stereo sound, but fullness, because advertising is a voice message against the background of soft music, and not a radio show.
For example, the O'Key supermarket uses up to hundreds of speakers with a power of 5 watts each - one building occupies more than a hectare of territory. Such systems are wound onto one monophonic high power amplifier. Or each column becomes active.
The brand of the manufacturer is a way to insure yourself against a fake. Give preference to well-deserved companies, for example, the Japanese Yamaha - it produced acoustics back in the 90s. This is not a requirement, but a wish for an inexperienced user who does not understand what brands and models from dozens of manufacturers are worth what and how they will justify themselves. In Russia, the choice of alternative manufacturers was so limited that experienced engineers independently developed their solutions based on ready-made ULF power up to 30 W and the same speakers. Such "home-made" sold to everyone.
The requests of even a single listener can change. Complete with active or passive speakers, along with an amplifier, a so-called equalizer is relied on. This is a multi-band volume control for individual bands (at least three) used in multi-channel acoustics. It sets the frequency response, which some listeners may not like. When you add “bass” (20-100 hertz) and high frequencies (8-20 kilohertz), this is done not only on a Windows PC, where Windows Media Player has a software 10-band equalizer, but also on real equipment .
Professional organizers of "live" concerts do not use any PCs - this is the lot of home users . At a concert performance by, for example, a worldwide rock band, electronic guitars and karaoke microphones, hardware mixing and physical equalization play a role. Only the 3D component is software - it plays a supporting role. The acoustic calculation of the concert hall and the meticulous selection of speakers for a multi-channel system will still be needed.
The size for the concert speakers does not really matter: the podium and concert hall are quite large, and “heavyweights” weighing about a car are not produced in the world of modern acoustics. One column weighs up to several tens of kilograms - 3 people can carry it. The total weight is determined by the mass of the magnet and the bearing rim of the speaker, as well as the wooden case, the BP transformer (in the active speakers) and the amplifier radiator. The remaining parts are relatively small.
The best material for the column is natural wood. Lumber based on it - for example, lacquered and painted chipboard - is a cheap replacement for oak or acacia, but the lion's share of the cost of the product is still concentrated not in the board. The value of the wood species does not matter - a wooden or a lumber plate should be sufficiently rigid.
In order to save money, MDF boards are often used - lumber, crushed to a fine powder, divorced with epoxy glue and several other additives. They are pumped into the mold under high pressure - after hardening the glue base the next day a solid and durable semi-synthetic board is obtained. They do not stratify over time, they are easy to decorate (MDF, unlike the roughness of a piece of wood or chipboard, has an ideal shiny surface), are facilitated by a box-like structure containing voids inside.
If you come across a column with a case made of chipboard, which the manufacturer has clearly saved on processing, then it is additionally impregnated with waterproof varnish on an adhesive basis (you can use parquet) and stained with several layers of decorative paint.
To avoid this, choose speakers with a case made of wood - it requires less maintenance.
The active speaker in the rear of the speaker is occupied by an amplifier with a power supply, for example, if it is a subwoofer for a multi-channel system. In order to avoid deterioration of sound at low and medium frequencies, it is fenced off by a partition made of the same material as the remaining 6 faces of the case. In cheap kits, this partition may not exist, in expensive ones, due to the seventh wall and the power supply with an amplifier, the mass of the subwoofer or broadband speaker increases by 10 or more kilograms.
Acoustics should be easily portable - it’s better to go a few extra times than to tear when carrying such speakers from the van to the podium and back. Concert speakers (at least 2) should be extremely high-quality in sound, easy to place and connect.
Do not purchase a multi-channel system - for example, for a school assembly hall if it is not needed.
About the features of active concert speakers, see below.