Whether you’re running a venue or putting together a mobile rig, you need a sound-reinforcement system that can meet your needs, both today and in years to come. We can comfortably categorize these systems into three groups: personal PAs, midsized PAs, and full-scale PAs. Personal PAs typically consist of single speakers or mini speaker arrays such as the Bose L1 series, which serve both as main speakers and monitors for each performer. Midsized PAs typically consist of a pair of stand-mounted speakers on either side of the stage plus simple monitor wedges; whereas, large-venue PA systems involve multi-speaker line arrays and extremely complex monitoring systems.

If you’re looking at PA speakers, then you’re likely putting together or upgrading a midsized PA system. These are the systems you find in most clubs, churches, and mobile DJ rigs. A modest midsized PA can cover a small audience easily, but with larger speakers and more powerful amplification, you can cover large indoor spaces and accommodate an audience into the 500+ range. There are many ways to build an amazing PA rig, and we hope this overview helps you sort out some of the major considerations.

Powered or Unpowered?

Neither powered (active) or unpowered (passive) PA speakers are categorically better than the other. It’s mostly a matter of personal preference, as well as the scale of the PA. For instance, extremely large PA systems are almost all composed of passive speakers fed by a rack full of amplifiers, because it reduces the weight of the speakers, the variation of sound between boxes, and the total current draw. On the other hand, powered PA speakers require none of the calculations involved with setting up unpowered speakers, offer greater speaker-by-speaker flexibility, and are considerably easier to reconfigure. Let’s take a closer look.

Powered Speakers

Powered speakers each feature one or more onboard amplifiers, eliminating the need for external amplification. Most powered speakers include simple frequency-adjustment controls, though it’s common to find onboard digital signal processing, especially on high-end models. This DSP often includes automatic frequency adjustments, speaker delay, feedback suppression, and other tools that allow you to set up quickly.

When it comes to midsized PA systems, powered speakers are far more popular than passive ones, primarily because of the flexibility requirements of midsized PAs. Whether you’re running an installed club system or a pack-and-go mobile rig, there’s a good chance that you’ll use your PA in a variety of different ways that require you to reconfigure your speakers.

Powered speakers make reconfiguring your system as simple as sticking a speaker where you need it and running cables to it. Their standalone nature also makes expanding your PA system easy, since you can always buy more powered speakers and add them where you need them. If you’re just starting out and only need a personal PA system, then you may want to consider picking up a single powered PA speaker like the JBL EON612, which includes a small mixer with a pair of microphone inputs onboard. That way, when you’re ready to step up to a midsized system, you can just pick up another one, and you’re halfway there. Likewise, the midsized PA system you invest in now can turn into your stage monitors as your system grows.

Powered PA Speaker Pros

Integrated power amplifiers provide optimal power to each speaker
Not needing to calculate loads makes adding/reconfiguring speakers easy
EQ controls allow you to adjust the tone of most speakers independently
Mixers allow some speakers to perform multiple roles in different setups
DSP on some models provides delay, automatic tuning, and network control
Powered PA Speaker Cons
Integrated amplifiers may add considerable weight to individual speakers
Overall power consumption can be considerably higher than traditional systems
Independent tone controls and electronics may make sound inconsistent or add noise
Individual speakers tend to be more expensive than unpowered equivalents
While sometimes daisy-chainable, each speaker requires its own power cable
Unpowered PA Speakers
Traditional PA systems center around one or more power amplifiers typically mounted in an equipment rack. While they’re less popular than they used to be, traditional PA systems have a lot going for them. For starters, the entire system may be far less expensive than one built around powered PA speakers, reducing the initial investment and lowering the cost of any parts that may need to be replaced. Without onboard amplifiers, passive PA speakers tend to be lighter than powered ones, which makes them particularly attractive for touring rigs.

The greatest objection to unpowered PA speakers is the need to calculate loads and total power requirements. It may seem baffling at first, but the learning curve isn’t particularly steep, and there are excellent tools that can make short work of it. In general, you want to buy a power amp that’s significantly more powerful than the rating of your speakers, as output clipping (a result of pushing the amp beyond its capabilities) is the number-one cause of blown speakers.

Crown XLS1002

The payoff for going with a passive PA speaker system is that you can keep the amplifiers in a rack by the board and retain full control of your speakers. Many modern amplifiers, such as the Crown XLS 1002, include sophisticated DSP onboard, which allows you to tune your entire system from a seat in the house, saving you a lot of setup time. You don’t need to run power to individual boxes either, and if you grab a powerful enough amplifier, adding speakers isn’t nearly as difficult as you might expect.

Unpowered PA Speaker Pros

Central power amplifier provides a central point for speaker control
Individual speakers tend to be less expensive than powered equivalents
Passive speakers are usually lighter than similar powered PA speakers
Not needing to run power to each speaker reduces setup time and cabling
Sophisticated DSP on some power amplifiers provides advanced tone control
Unpowered PA Speaker Cons
Calculating resistance and load comes with a bit of a learning curve
Reconfiguring and adding speakers requires additional calculations
Multiple power amplifiers may add up to a single heavy rack
Daisy-chained speakers don’t usually offer independent volume controls
Lower popularity means there are fewer models/options to choose from
Go to the Sweetwater live sound sale page
Power vs. Output
There are a lot of factors that go into how loud a speaker is, including the size of the speaker and the efficiency of the voice coil. One of the first traps to avoid when looking at PA speakers is confusing power with actual output. While power does play a role in the overall volume, the maximum/peak SPL is usually a better indicator of the actual volume of any given speaker. Another factor worth considering is the speaker’s coverage angles. A powerful speaker with a narrow coverage angle may be perfect as a stage wedge, but a less powerful speaker with a broader coverage angle will serve you better as a main speaker.

Driver Configuration

It’s easy to assume that bigger is better when it comes to PA speakers. That is, in fact, often the case, but there’s a bit more to speaker configuration. First, consider the actual speaker arrangement. In the case of a PA speaker that only has a single full-range driver, that driver has to cover the whole frequency range. A small speaker that’s great for high frequencies won’t reproduce low frequencies well, and a large speaker that’s good for lows won’t reach the upper end of the spectrum.

As you can see, a single driver isn’t efficient on its own, and single-driver speakers are limited to a narrower frequency band. When you split the frequency range between a high-frequency driver and a low-frequency driver, each speaker can do a better job covering a small band, increasing both the output and the frequency range at the cost of a bit of extra amplification. Split the signal into three parts, and the overall efficiency, frequency range, and potential output expands again.

Monitor Speakers

At this point, you might think that 3-way speakers such as QSC’s KW153 are inherently superior to most other speakers, and if you’re only considering your PA system’s main speakers, you might be right. However, their size alone would make them a horrible choice for stage monitors. But that’s not the only thing that makes bigger speakers less ideal for stage monitoring.

Given that low-frequency buildup is a serious problem onstage — particularly on hollow stages — you probably don’t want to use 15″ low-frequency drivers for monitoring. In fact, monitor speakers with a slightly narrow coverage angle and an emphasis on upper-midrange frequencies will do a better job punching through the sound onstage. In general, it’s better to have more focused stage wedges than to have fewer monitors with broader coverage and deeper lows.

Want to know more about monitors? Take a look at Sweetwater’s Live Sound Monitors Buying Guide.

Subwoofers

Many people relate the idea of subwoofers with big booming bass, and while that’s great for dance music, it’s not exactly ideal for many other genres. However, exaggerated low end is only one use for subwoofers. The more important use of subwoofers is to allow your mains to work more efficiently. It’s just like adding another speaker to your mains (see the section above on driver configuration). In fact, most modern subwoofers include a crossover circuit that splits the signal into the lows heading to its speaker and the mids and highs going to your mains. Low-frequency sound is not as directional as high frequencies are, so you can usually get away with a single subwoofer such as the Turbosound iQ18B, which features two input channels, summing the bass to mono and sending the stereo signal to both of your mains.

All-in-one PAs

There are several all-in-one PA systems, such as the Peavey Escort 6000, that do an excellent job covering all the basics and are incredibly portable. These systems are almost all built around a powered mixer (combination mixer and power amp) and a pair of matched speakers. What’s great about them is that once you outgrow them, you can still put them to use as stage monitors, and you can keep the monitor mixer onstage if you want to let the band adjust the mix.

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