What is a point source?

A point source is a speaker set designed to behave as closely as possible to a single sound source with a specific directional characteristic.

In practice, this can be:

• a single full-range set,
• a broadband set working with a subwoofer,
• larger, high-performance point source concert system.

The most important feature is that one set must cover a specific sector of the audience.

If its directionality matches the geometry of the room, a point source can be very effective. It does not require building a long array or precisely setting angles between multiple modules.

Point source works particularly well where:

• the audience is relatively close to the system,
• the difference in distance between the first and last row is not very large,
• wide coverage is needed,
• the height of installation is limited.

One should not equate point source with a "small speaker." There are designs of this type capable of operating at very high SPL and at large events. 

How does a line array work?

A line array is a system consisting of multiple modules designed to work together in one array.

The goal is not just to increase the number of speakers. The modules should work so that the entire array creates a controlled source with a specific directional characteristic.

In practice, the following are important:

• the number of modules,
• the length of the entire array,
• the spacing between sources,
• the angles between modules,
• the height of suspension,
• the frequency,
• the distance from the listener.

The line array system allows shaping vertical coverage through the geometry of the entire array. The upper modules can cover further sectors, while the lower cover the closer audience.

This allows for a more controlled distribution of energy in large and deep spaces.

However, this does not mean that every set of several modules automatically behaves like an ideal linear source. 

The most important difference: control of directionality and coverage

The most important difference between line array and point source is not that one system is "stronger." It is primarily about how energy is controlled in space.

Point source usually has a defined characteristic of a single set. If a larger area needs to be covered, additional sources can be used, but their overlapping requires control.

Line array allows shaping vertical coverage through the length of the array and angles between the modules.

For example, in a deep audience, one can:

• aim part of the array further,
• part into the middle zone,
• lower modules into the first sectors.

This provides greater control over the level difference between near and far listeners.

However, one should not look solely at the vertical. The horizontal directionality of a specific system is equally important. If the array has too wide an angle relative to the room, it may unnecessarily send energy into the walls.

What happens to the sound level with distance?

In an ideal free field, a point source loses about 6 dB with every doubling of distance.

In the case of an ideal, infinitely long linear source, theoretical drop is about 3 dB with doubling of distance.

However, a true line array is not an infinite linear source. It has a finite length, and its behavior changes with frequency and distance.

That is why the popular statement "line array loses only 3 dB, a point source 6 dB" is too much of an oversimplification.

In a real system:

• low and mid frequencies may behave differently than high,
• with distance, the character of the field changes,
• the length of the array affects the range in which the system behaves more like a linear source.

That is why line array systems are designed using manufacturer software, rather than solely based on a simple equation.

When is a point source a better choice?

A point source is often better when a single set can adequately cover the needed area without the need to build a large array.

Typical applications include:

• small clubs,
• short rooms,
• corporate events,
• small concerts,
• side stages,
• fill systems.

In a small club, a small line array can be difficult to properly suspend. If the array is very close to the audience, the distance differences between individual modules and the listener can be large, and the physical length of the array may be inadequate for the space.

A good point source set at the right height can then provide simpler and more predictable coverage.

Another advantage is the reduced complexity of the system. Fewer modules typically mean:

• simpler rigging,
• shorter setup,
• less weight,
• fewer amplifier channels,
• smaller transportation requirements.

That is why the sound system for a concert in a club or concert hall should not be automatically based on a line array just because a band is performing on stage.

When does a line array provide a real advantage?

A line array provides a real advantage when it is necessary to cover a deep audience, control vertical dispersion, and limit large differences in level between the front and back.

Typical applications include:

• large outdoor concerts,
• festivals,
• halls,
• large performance venues,
• events with grandstands.

A line array system allows for more precise energy distribution at different distances.

With the appropriate height of suspension and length of the array, it is possible to limit the amount of energy reaching areas outside the audience, such as the ceiling of the hall.

In outdoor settings, the benefit is also the ability to more effectively serve distant sectors without extreme increases in level at the front rows.

That is why when choosing a sound system for a large outdoor event the geometry of the array is one of the key elements of the design.

Why do several modules not always create an effective line
array?

Several enclosures suspended one below the other do not guarantee the behavior typical of a well-designed line source.

The effectiveness of the array depends on many parameters:

• the physical construction of the module,
• the mutual distances of the transducers,
• frequency,
• number of elements,
• lengths of the array,
• angles between the modules.

A too short array may not provide adequate control in lower frequency ranges. At the same time, increasing the angles between elements may change the way sources interact at high frequencies.

That is why manufacturers design line array modules as part of the entire system and provide tools for configuring the array.

It is a mistake to think:

"four modules = small line array, so it will be better than point source".

The correct question is:

"will this specific length and geometry of the array provide the necessary coverage in this space?".

Small club, hall, outdoor – comparison of three applications

The choice of system is best seen in specific types of spaces.

In a small club, the most important thing is usually control of directionality and limiting energy hitting the walls.

In the hall, the importance of the audience length and reverberation is growing. The ability to limit the energy sent to the ceiling may favor the array.

At a large outdoor event, a line array can provide a real advantage in serving a deep audience, but there too the configuration must result from the design.

Art-Live selects the system for a specific space, instead of assuming one type of PA as the right solution for every event.

Costs, rigging, transport, and assembly time

A line array is usually more logistically complex than a simple point source system.

It may require:

• a greater number of modules,
• flying frames,
• structures or suspension points,
• motors,
• a greater number of amplifier channels,
• a greater amount of cabling,
• a larger crew.

There is also the mechanical design and control of acceptable configurations by the manufacturer.

A point source can be much simpler if several sets provide the required coverage.

However, this does not mean that a point source is always cheaper. In a very large venue, trying to create a distributed system from multiple large sources can also generate significant costs.

Therefore, the price should not be a comparison:

"point source vs line array."

It should result from a complete configuration that fulfills a specific task.

Why is system prediction more important than the name
of the technology itself?

Prediction allows us to assess what the system will do in a specific space even before its installation.

In the manufacturer's software, you can model:

• the geometry of the audience,
• the position of the system,
• the height of suspension,
• the angles of the modules,
• the distribution of SPL,
• the coverage in different frequency bands.

This allows you to compare, for example, two variants:

• a point source system,
• a line array.

It may turn out that a more prestigious-looking array gives less even coverage than a properly selected classic set.

It can also be the other way around: a single point source may provide excellent results at the first 20 meters but struggle with the further part of the audience.

Technology is just a tool. The quality of the project depends on how it is applied.

How to professionally choose between the two constructions?

The choice should start with defining the task, not with indicating the type of speaker.

First, it is necessary to determine:

• the size and geometry of the audience,
• the distance from the first to the last listener,
• the width of the audience,
• the height of possible mounting,
• the required SPL,
• the nature of the event,
• the acoustic limitations.

Then you can prepare system variants and check their coverage.

If a point source provides an even level and appropriate directivity, there is no technical reason to choose a line array solely for the name.

If, however, the geometry requires a large range and precise vertical control, a line array system may be a significantly more effective solution.

The best choice is therefore the one that accomplishes the task with as simple a controlled configuration as possible.

Summary

Line arrays and point sources solve a similar problem using different methods. A line array system provides great control over vertical coverage and can give an advantage in deep spaces, halls, and large outdoor events. Point sources often perform better in small and medium venues, where a single set can effectively cover the entire audience.

However, technology should not be chosen based solely on the scale of the event. A line array that is too short or poorly suspended may perform worse than a properly selected point source.

The most important factors are the geometry of the audience, directionality, height of installation, required level, and prior system prediction. The selection of sound reinforcement should result from the specific space, not from the assumption that a line array is inherently a more professional solution.

Frequently Asked Questions