Thinking inside the box - Can prefab work?
By: Paul Sonoda
It used to be, getting a great sounding subwoofer system required having an enclosure custom built. You needed the professional expertise of the high-end installer. The installer, armed with the technical support from the manufacturer had the tools and skills to build the perfect enclosure. Today you have another choice: prefabricated enclosures. Prefabricated enclosures are enclosures built by someone other than the installer at the time of installation. Is prefabricated enclosure right for you? Can prefabs work in your stereo?
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topWhy Prefab?
There are many reasons for using prefabricated enclosures. The most obvious is convenience. First there is the convenience of time. You want to get your stereo system installed in a hurry. Whether you perform the installation yourself or you have your system professionaly installed, building an enclosure takes time, tools and space you may not have. With prefabs, you can install your system quicker and easier. Not to mention you won't need to buy a table saw!
Second, there are certain vehicles out there where building enclosures are difficult and time consuming. In fact they are down right a pain in the butt. Given this fact, it might be too expensive or take too much time to have you build a custom enclosure for these vehicles. This is where prefabs can really shine.
Deconstructing Prefab
The most common materials used in prefabricated enclosures are particle board, MDF, Fiberglass and composite resin. Particle board is usually the least expensive type of material. You can recognize it by the larger chips that are visible in the sheets. While less expensive than MDF, it is usually less sturdy and more susceptible to damage and wear. Most typical finish for particle board enclosure is some sort or trunk carpet or trunk liner.
MDF is the most common material used in prefabricated enclosures. It is dense and quite sturdy. It also cuts and machines well providing for a cosmetically appealing, strong enclosure. Most high quality manufactures of prefabricated enclosures use MDF. Just as important as the type of wood you use is the method on how it’s constructed. The quality of the enclosure depends on the type of joints (lapped and or dadoed) used and how much internal bracing (if any) is used. Lap and dado joints are construction techniques designed to increase the surface area of joints and hence the strength of the enclosure. Finishes for MDF enclosures include trunk carpet or trunk liner as well as paint in higher end enclosures.
Finally, there are fiberglass and polymer resin type enclosures. These enclosure materials are generally reserved for vehicle specific enclosures. Companies like JL audio and MTX have designed custom shaped enclosure designed to give the best audio performance while utilizing wasted space in the vehicle.
Potential prefab problems
As always, there are things to consider when going the route of prefabs. The most obvious problem is one of sound quality. Will the enclosure maximize the performance of the woofer or will it sound bad. Will the enclosure tuning create power handling problems? Contact your woofer manufacturer to see if they have any experience with the enclosures. Before buying an enclosure, inspect it or see if you can hear the enclosure before you buy. The other potential problem is the construction reliability. Even if the woofer sounds great, you would be most upset if the enclosure cracked or came apart under normal use.
How to choose the right prefabricated enclosures
Choosing the right prefabricated enclosure depends highly on your system design goals. Choose enclosures that are designed or optimized for the woofers you have. This is highly important to the sound quality of your system. There are several enclosure manufactures that have built enclosures for specific woofer lines. Companies like SubZone, http://www.subzoneusa.com, and Q Logic, http://www.qlogic.ws, have enclosures reference charts that help you select the right enclosure for the woofers in your store.
Second if your vehcile makes it difficult to fit a traditional style enclosure, choose prefab. These enclosures may cost more but are typically well designed for fit and sonic performance.
Conclusion
Take advantage of prefabricated enlcosures. They are excellent solutions when you consider the time saved in installation. For difficult to build vehicle specific enclosures, get spec sheets that outline what the performance expectations will be, how loud will the enclosure play and what it looks like in the vehicle. These enclosures are designed to use "wasted space" inside a vehicle. In many cases, there are vehicle specific enclosures that will become nearly invisible while providing great bass. This is highly desirable to anyone looking for a great sounding stealth system.
Some say that clothes make the person. In car audio, we say that enclosures make the subwoofer. Prefab enclosures gives you the flexibility to install great sounding systems in your vehcile without the need for a table saw.
