The biggest factor in determining your guitar's sound is going to be the woods it's crafted from. Some woods are known for a very 'bright' sound that accentuates the high end frequencies, and others with more porous and wide grain will tend to have a much more rich and low end/bassy sound. A general rule of thumb is 'the lighter the wood, the brighter the tone'.
Listed below are some of the most common tone woods and how they affect the sound of your instrument.
Noted for it's bright, expressive, and resonant sound, spruce is one of the most commonly used woods for acoustic guitar tops and bracing. Typically paired with a darker sounding wood such as mahogany or rosewood for back and sides for a remarkably even sounding instrument that brings out the best of high and low frequencies.
A favourite top wood amongst classical players and steel string players alike, cedar's darker colour also reflects in it's sound. While not being as bright as spruce or maple or as bassy as mahogany or rosewood, cedar finds a comfortable middle ground, bringing out the best of both of both worlds while having a remarkably rich mid range.
Common as both a top wood, as well as among the most common woods for backs, sides, and necks, mahogany is a very dark and stable wood which has a very rich, warm, and deep low range. While it's commonly used in conjunction with spruce, cedar or other light woods for a balanced sound, full mahogany instruments offer an unparalleled richness ideal for finger picking.
Visually stunning and highly sought after, rosewood's tonal properties are similar to that of mahogany in that it is very bass responsive. This along with it's gorgeous streaks have made rosewood a highly desirable wood for acoustic backs and sides, as well as fretboards and bridges. Rosewood is typically more expensive than mahogany to source and was incredibly limited for use upon becoming endangered. Many companies have shifted away from its use, however is still seen on higher end models.
Generally used as back and sides on acoustics, maple is another visually appealing wood. You’ll often see flame maple (tighter and straighter grain) and quilted maple (wider and curvier grain), however standard/plain maple is not uncommon and looks visually similar to spruce. Maple is known to have a distinctly bright tone, which cuts through the mix well while performing.
As seen on the top of the Fender FA-235E Concert
Visually gorgeous, koa is dense tropical wood that originates from Hawaii. The wood itself has a look that is very distinguishable, with an orange hue and a lot of figuring in the grain. Tonally, Koa sits in the realm of mahogany’s tone, with the high-end bite that you get from maple. It’s another sought-after wood that is usually found on mid-upper range models of both electric and acoustic guitars.
Due to the limitations placed on rosewood, walnut is becoming more popular on acoustic guitars. Walnut's dark and less streaky appearance, and more plentiful availability have made it an ideal replacement on many guitars that have previously used rosewood. The tone is relatively brighter than rosewood so has been used as a replacement for fretboards as well as backs and sides.
Known as a less expensive subsidiary to mahogany, sapele is very similar in looks and tone to that of its brother. It has a very noticeable mid-low range tone and has a slightly brighter high end to that of mahogany due to being a higher density. Being a relatively inexpensive replacement for mahogany, it’s also commonly used for ukuleles as well.
As seen on the back and sides of the Martin D-12E
Ovangkol is another more-sustainable alternative to rosewood and mahogany. Visually it looks like a cross between mahogany and koa, but tonally it sounds closer to rosewood, having a little more of a focused mid-range to it. It can be found on more limited edition models and mid-to-upper range models.
As seen on the back and sides of the Fender CD-140CE
Visually and tonally among the darkest woods used for instruments, ebony is a stunning and highly sought after wood with a very pronounced and clear bass range. Being quite expensive to source, ebony is typically used for upper end guitar fretboards, and occasionally for backs and sides.
Guitars come in many different shapes and sizes. Body size not only affects the overall playability of a guitar, but also drastically affects the overall sound as well. Manufacturers will sometimes use different terminology and have slightly different dimensions. Below are some of the most common sizes and names.
The most common of all acoustic body styles. The dreadnought is known for its large amount of projection and volume, while still being able to handle softer finger picking nicely as well. A great all-around acoustic with plenty of options at every price point.
Stylistically similar, but having slightly larger upper and lower boughs than the concert/folk size, the 000 is still a great for smaller players, or those who enjoy fingerpicking. The smaller body of a 000-size guitar makes it extremely comfortable to play without sacrificing as much volume and low end. Though they still offer slightly less volume than a dreadnought due to the smaller body, they make up for it in comfort & a nice presence in the high end voicing. The 000 name and size is much more commonly used on higher end acoustic brands like Martin.
With slight variances in size and names across brands (notably Takamine's 'New Yorker' size), the parlor size is the smallest body size among full size acoustic guitars. With very narrow boughs and typically having a slightly shallower depth, the parlor is considered one of the best guitars for finger-style playing for it's chimey upper range.