Choosing the right acoustic can be tough, especially these days, when there are so many styles to choose from. Do you buy a cutaway or a non-cutaway? Do you need an acoustic with a piezo pickup for playing live, or are you just going to be strumming in the backyard? What kind of body shape do you want: a jumbo for big, fat bass tones, or a roundback for playing comfort? Let's tackle some of these questions and see if we can clear away some of the mist.
Shapes & Sizes
Many guitar manufacturers distinguish their instruments with signature elements like a unique bridge shape, inlay work, or even the cut of a pickguard. Still, you'll find that acoustics come in a few general shapes. Your selection will depend how comfortable you feel holding the guitar, the style you play, and how you like the sound. To get a better idea of a guitar's sound, let someone else play while you sit in front of the guitar and listen. Chances are you won't have any trouble giving a salesman the opportunity to strut his stuff. You can cut your shopping time way down once you know what body type you're looking for. Here are a few of the most common types.
Dreadnoughts have been among the most popular acoustics for years. Their big bodies and strong sound make them popular with everyone from "Kumbaya" strummers to unplugged rockers to flat-picking country kickers. Dreadnoughts have square shoulders on the upper and lower bouts, and are fairly wide at the waist. They project a loud, full sound when strummed or picked.
Classical guitars are named for the genre that made them popular. Typically strung with nylon strings, they are a much different animal than their steel-string cousins. Classicals are usually compact in size and feature wide necks - ideal for fingering in traditional style. While excellent for fingerpicking or even flat-picking arpeggios, you won't get a glistening strum from these classy acoustics; they're better suited to straight-up classical, Spanish, and Flamenco styles.
Concert acoustics are steel-string guitars that tend to have approximately the same dimensions as a classical. Their small bodies keep them from being especially loud, but they're popular with fingerstylists for their manageable size and often warm tone. Concert acoustics are typically narrow at the waist and have nicely rounded bouts.
Jumbo acoustics have gained more fans in recent years, reviving a size popular in jazz's pre-electric days. Slope-shouldered and narrow-waisted, jumbos feature a lot of body behind the bridge, which gives these guitars a nice boost on the bottom end and a big, round tone. A well-made jumbo can project almost as strongly as a dreadnought and still have the warmth and evenness of a concert acoustic.
Parlor guitars are narrow at the shoulders, narrow at the waist, and conspicuously smaller than the guitar's mentioned above. Their diminutive size means the sound is "smaller" as well. But parlor guitars are often noted for their velvety tone, and many people find the size and shape easier to handle. Parlors were popular with many early blues players, and are still the axe of choice among many fingerstyle players.
The Cutaway Decision
Cutaway acoustics are everywhere these days, but are they for you? Traditional players will probably opt for non-cutaways, which offer the maximum interior space of the acoustic box and, therefore, the biggest sound. The modern picker will sacrifice some of this acoustic cavity to get more upper-fret access. My rule of thumb is that if you're going to play mostly on the porch or in your living room, skip the cutaway. Only a full-bodied acoustic will deliver a full range of tones, and, to my ears, bass response is the first casualty in a cutaway. For true unplugged situations, a good non-cutaway will blow away even the best cutaway almost every time. It's simply a matter of physics.
However, if you're planning to plug in for gigs or recording, try a cutaway, since you can electronically adjust the bass EQ on your mixer, amp, or effects system. Again, this is just my bias. If you're concerned about bass response when playing it acoustically, you might want to check out a cutaway with a jumbo body style; the added cavity space of a jumbo can help make up for the space that has been "cut away." Try out both body styles and ask other players to help you decide which way to go on this crucial issue.
Just as you have to decide about cutaways, thinking about electronics is another major factor. If you want the ability to plug into an amp or PA, chances are you'll be interested in piezo pickups (usually right under the bridge saddle) that create an acoustic tone. You can also opt for a detachable soundhole-mounted magnetic pickup. Some players think magnetics don't sound as good as piezos, but that's a question of taste.
Various pros also employ internally mounted microphones which feed out to a hi-fidelity XLR jack. You can even find players who use combined systems, such as a magnetic pickup and a microphone, and then mix them to find the most acoustic-like balance.
Your options also include using either an internal pickup that feeds to an external preamp or forsaking pickups altogether for that old-fashioned solution: play in front of a microphone. The rationale here is that installing a big pickup/preamp system with three-band EQ, controls, and a battery compartment can undermine an acoustic's tone, since a large portion of side wood has to be cut out to install the unit (you can see that on guitars that have EQ sliders and volume controls located on the upper side of the body). But if you want a basic, very usable system, the popular choice today is a piezo system that features a 1/4" output jack on the back or side of the body. While they are available with or without batteries, those with batteries will provide some sort of onboard EQ and volume control. Think about how much control you really need.
Almost everybody knows that, for unamplified playing, you want a solid-top acoustic, not one with a laminated veneer top (essentially, thin, glued layers of wood). Functioning much like a speaker, an acoustic's top is crucial to producing the guitar's tone, and for the best tone you want a solid piece of wood that resonates as organically as possible. In the upper echelons of guitars, you'll almost always get a solid top, and these days, many mid-price guitars have them, too. But check it out for yourself. On a solid top, you should be able to see the end-grain of the wood around the soundhole. If the wood looks sandwiched or is covered up with unnecessary decoration, start asking questions. Guitars with painted tops pose an extra problem since you can't see the edges. In that case, check the product literature and make sure it indicates that the model has a solid top. The bottom line is that solid tops move and resonate better, and therefore create a better tone; laminated tops don't move as well and aren't recommended for playing unplugged.
On the other hand, laminated tops seem to work fine for any guitars with built-in pickups and preamps. This is largely because the top isn't as critical to producing tone. When going through a PA, mixer, or amp, the pickup/preamp setup is hard at work creating your sound, so the top isn't necessarily as crucial as if you were recording via microphones. For mics, go with a solid top, but if you're going to pump up the volume, you can probably go with either a solid or laminated top. You may have also noticed that some guitars have veneer sides and backs. Since the function of these parts is more about support than creating tone, veneer sides don't appear to be a negative factor for most players. But if you're a finicky tonesmith who's going to be recording on a high-end system, you may want to spend more cash and buy completely "all-solid" wood acoustic.
Many acoustics look beautiful on the outside, but inside may be another story. On lower-end guitars, you may see globs of glue on the inside joints and less-than-perfect brace work. While the body should be strong enough to do the job, you can't expect miracles when you're spending $450 on what is actually a carefully engineered wooden box. Look inside a $2,000 acoustic and it should be as gorgeous in there as on the outside. On low- to mid-price acoustics, however, you can expect the occasional dash of sloppy fretwork and neck joints, but then again these are essentially mass-produced acoustic guitars. In the end, you're probably best off with a guitar that is visually appealing to you and seems to have a durable finish. Or course, as with any guitar purchase, you've got to find the guitar that looks, feels, and sounds the best to you. Follow your heart... but use your mind, too.
You now have a good basis to begin exploring variations of your own using the notes emphasized in each lick. By the way, the other true "blue note" is the microtone between the b7th and the major 7th.