There was a time when outdoor speakers were hardly worth the effort, providing about the same level of quality as a battery powered boom box - without the portability! Fortunately, those days are now officially over and, as the boom box slowly bites the dust, the time has come to have a fresh look at alternative ways of getting music out of the lounge room and into the back yard. This guide covers all the main features to look for in an outdoor speaker system.
Independent and integrated systems
There are a couple of different ways you can rig up outdoor audio setup. One of the biggest deciding factors is whether you want the sound system to be driven by the lounge room Hi-Fi, or whether you want an independent audio source. If you want to share the lounge room Hi-Fi for both indoor and outdoor use (that is, if you want an "integrated" system), you will need to make sure your amplifier supports an extra pair of speakers. Most amplifiers have A and B speaker outputs for exactly this reason, although if you are already running two sets inside, you may need to consider an alternative configuration. Another factor to consider when planning an integrated outdoor system is the distance and feasibility of running speaker cable. While it is possible to run cable for 50 metres or more - provided you use high quality shielded cable - it just may not be practical to do so. If you have underfloor access, then running cable is the best option. Otherwise, you may need to consider a pair of wireless speakers. This will significantly affect either the price or the quality of the system you choose.
If you are thinking of setting up an independent outdoor sound system, however, you have a few more options. This will mean the extra expense of purchasing a dedicated amplifier, but the added flexibility means that you probably won't have to worry about running cable in awkward places. Instead, you can think about whether you want an amplifier that is located indoors that drives the speakers, or whether you want speakers that have an amplifier built-in.
Powered and un-powered systems
Powered or "active" speakers are those that incorporate a built-in amplifier. The advantage of using powered speakers is that you can control the volume and input source from outside - where you will be listening to them. The downside is that you need to plug an audio source directly into the speakers. This may be perfect if you only ever intend to use a portable media player, but it can be problematic if you want to plug in a CD player that runs on mains power. Not only will your amplifier controls be outside while the CD player controls are inside, but you'll need an audio cable connecting the two. Stereo RCA leads are considerably more expensive than speaker cables, so a powered system can be inconvenient if it is permanently installed. Alternatively, an FM transmitter can be used from inside the house to beam any audio source to a standard FM radio which is connected to the outdoor speakers. These transmitters range from $30 to $100 and you will need the best one you can get if you want to ensure reasonable quality, as they are subject to considerable hiss and noise. The real benefit of a powered system, however, is that it is portable and can be stored inside while not in use. Not only will this prolong its lifespan, but it means you can use it in other locations. Powered systems range greatly in power and quality, so definitely compare a few in advance. You will need at least 30 watts to get acceptable amplification, and look for something that is 2-way with equalisation controls (ie: bass, middle and treble knobs).
An un-powered pair of outdoor speakers will provide you with much better quality for the same price, as you won't be paying for compact amplifier technology. Un-powered speakers are suitable for both integrated and independent systems, both of which require you to run speaker cable into the house. The cheapest un-powered speakers you're likely to find start at about $70, although you're up for at least $300 if you want something that is remotely comparable to standard indoor speakers. Comparatively, powered outdoor speakers will set you back at least $200 with around $500 being more likely if you want something that sounds better - as well as louder - than your old boom box.
Most outdoor systems are designed to be permanently or semi-permanently installed. The higher they are off the ground, the better the effective range will be. Consequently, wall-brackets are usually the best bet. This also keeps them out of reach of children, thieves and animals. If possible, mount them directly onto brick or wooden walls, avoiding aluminium and gyprock surfaces. Not only will these affect the sound, but they may not be strong enough to support the speakers for any length of time. If possible, mount them under an awning or other covering. The more protection you can provide them from the elements, the longer they will last. If you aren't going to be able to keep them covered, make sure the model you buy is rated for extreme conditions. If you're near the beach, you may also want to consider a pair that is rated for marine conditions, as the salt water can dramatically reduce their lifespan. If you can keep your speakers out of the rain and direct sunlight, you should get at least 10 years out of them. Speakers rated for use in marine and other extreme conditions should last even longer unless they are exposed to extreme conditions.