Basses - Different Construction Techniques
When you're looking to purchase a bass, it's very helpful to know the different construction types that are available, and why you might choose one over the other. Here is a brief description of the most common types of basses, and what that means to you.
Laminated Basses (aka "Plywood")
LAMINATED basses are sometimes referred to as "plywood" basses -- and these basses are built that way for very good reasons. Fully carved basses can develop cracks at times during their lives. Due to seasonal or environmental changes in humidity, the large pieces of wood in a bass can shrink (low humidity) or swell (very high humidity), resulting in cracks or seam openings that require repair. That's why laminated basses were developed. Keep in mind, though: while the process of making builder's grade plywood and that of creating fine wood laminates is similar, basses are not built of the same grade of stuff you see at your local home improvement warehouse! Rather, high-quality, thin maple laminates are pressed and glued for the back and sides. Maple and spruce are the traditional woods used for fully carved basses, and likewise, most instrument-makers use laminates of the same woods for their laminated basses as well. The top and back are pressed over a form to create the desired shape.
Laminates do not shrink or expand like solid wood, so variations in humidity are not a problem. And as it is with furniture made from laminates rather than solid wood, they are less expensive to make -- and thereby less expensive to purchase, as well. Laminated basses also tend to have lessened potential for feedback, as the top is not as sensitive. Because of this, they are often greatly preferred for "louder" styles of music, such as rockabilly. Along the same lines, because of their less "live" tops, laminated basses have a tendency for a more percussive attack than that of carved basses, making them potentially better for slapping as well as for someone who does mostly pizz work.
This being said, there is absolutely no rule that a laminated bass cannot sound great with a bow! Though, you should keep in mind that -- all else being equal -- a laminated bass might not produce the same level of tonal complexity that a fully carved instrument can. Although most low-end or entry-level basses are of laminate construction, it is important to note that every instrument is different -- so you shouldn't write off the viability of playing a laminated instrument because you were underwhelmed by the cheap, poorly set up model that you thumped around on at your local chain superstore. There are some very fine laminate basses on the market today.
BOTTOM LINE: You might choose a laminated bass if you are on a budget, play bluegrass, rockabilly, slap, or any high volume music, and are looking for a durable, lower-maintenance instrument that you can keep for a lifetime.
Fully Carved Basses
FULLY CARVED describes a bass which is a solid wood instrument with no laminated surfaces. Both the top and back are carved (sometimes the back might be a solid wood flatback), and the side ribs are made of solid pieces of wood. Those basses that are considered the finest in the world are usually fully carved, but that doesn't mean that the best sounding bass for a particular style is a carved instrument. However, quality carved instruments deliver a more sophisticated result with more complex response, and richer overtones. Many people describe the difference between a plywood and fully carved bass is akin to taking a blanket off of the instrument. Additionally, new carved basses are commonly known to "open up" with frequent play, a phenomenon wherein the bass actually begins to sound better and better the more it is played; to oversimplify, think of it as a similar process to "breaking in" a baseball mitt by simply using it.
Keep in mind that the tone quality advantages will come with a trade off in durability, as the more "live" solid top means more of a likelihood for cracks developing over time. Such cracks are to be (eventually) expected with a fully carved instrument, and all good luthiers are experienced at repairing such cracks.
Carved basses are also more sensitive to temperature and humidity changes. The bass may "swell" and "contract" with the change in seasons, or in particularly dry or wet climate changes.
Carved instruments are usually preferred by orchestral players, as well as many professional jazz players or in any playing situation where the best possible sound is paramount. Costs are usually a good bit higher for carved instruments, compared to laminates - not only is the hand-carving of a solid wood bass time- and labor-intensive, but there is also a lot of quality wood "wasted" when it's carved away.
BOTTOM LINE: You might choose a Carved bass for the most tonally "complex" sound on both Arco and pizzicato playing. But know that there is more "care and feeding" involved to keep the bass healthy.
Hybrid Basses
HYBRID basses (usually) combine a fully carved top with a laminated body and sides. Using solid wood for the top, which is one of the most tonally important parts of the instrument, can often provide many of the tonal benefits of a carved bass -- while having a price point and maintenance level that is more like those of a laminated one. Solid wood "moves" more than laminate layers, so the response of a hybrid can be somewhat more immediate and tonally complex.
This alternative to a laminated instrument does require a bit more attention in order to protect the carved top (vs. a laminate bass), although thanks to the laminated back and sides you will generally encounter fewer cracks, even on the top, from expanding and contracting due to humidity and/or temperature.
Hybrid basses, which aren't usually as common as laminated or fully carved basses, offer a middle ground between the durability of a laminate bass, and the tonal complexities of a fully carved instrument. They are a very good option for many styles of music, and are often favored by intermediate and advanced players. (Which is not to say that they are not suitable for a beginner, as well.)
BOTTOM LINE: You might choose a hybrid if you want a more "carved bass-like" refined tonal response in a "laminated-like" more durable package. They are suited for pizzicato (plucked) sustain and for Arco (bowed) response.