I am referring to guitars of the same body type equipped with identical strings. Do different materials influence sound positively by such an amount that a non-professional could see the extra value for the extra money spent? I am excluding aesthetic differences.
The one thing that will make the biggest difference in the way an acoustic guitar sounds, is the material used to make the top which is commonly referred to as the "soundboard".
The body of an acoustic guitar consists of the top (which has a sound hole cut into it), the back and the sides.
Less expensive acoustic guitars will generally use what is known as a laminate "wood" for constructing the the entire body of the guitar, including the top.
A solid top is milled from a solid piece of wood that is large enough to be cross cut into pieces that can be used for the top of the guitar. Laminate is less expensive because it is made from thinner (less expensive) pieces of wood pressed and glued together, usually with the grain of each layer running opposite one another to provide more strength.
The reason we say the top is the soundboard - is that most of the sound (not quite all) results from the vibration of the top- which creates sound waves much the same way as does a speaker vibrating. The vibration of the strings (which would make very little noise by themselves) is transferred to the top through the saddle (on which the strings rest) and the bridge (directly under the saddle and glued firmly to the top).
A well made and properly braced solid top will vibrate more freely and resonate more than will a laminate top. The glue in the laminate top tends to dampen the vibrations, and the layering with opposing grain, while adding structural stiffness to the laminate top, tends to create a sonically stiffer top as well (less vibration = less sound and less sustain).
While it's no guarantee of the overall quality of the workmanship and build of the guitar, in general, you will only find solid tops on the higher end (more expensive) of any guitar manufacturer's line of guitars.
Solid top guitars will cost more, but if there is any one factor that will most predictably result in a better "sounding" guitar, a solid top verses a laminate top creates the most reliable line of demarcation.
Solid back and sides are reserved for even more expensive guitars, but do not make nearly as big an impact on the sound of the guitar as a solid top will.
So a good step up from in terms of sound - from an all laminate body acoustic guitar, would probably be to one with a solid TOP - with laminate back and sides. Next step up from there, is all solid top, back and sides - but the more solid wood you have in your guitar body, the more susceptible it becomes to the environment (read more maintenance required to protect your guitar from unfavorable conditions).
Be aware that the top material (spruce, cedar, mahogany, maple, sapele, koa, etc.) will affect the tone of the guitar. If you elect to go with a solid top, if there are different wood types offered within your budget, you may want to listen to the way the top wood colors the tone to see which sounds you prefer. But that is another discussion altogether.
"cheap" does not only implicate sound quality.
Really cheap means CNC milling from cheap wood. Since that means that the wood is not worked with considering its strengths and grain and is not yet stable, the result will not resonate well and/or warp so soon that the instrument becomes unplayable.
Then we have playability: how far do you have to press the strings over higher frets? For a good instrument, strings will not snare, yet you still only have to press down very little.
A medium instrument requires more work with your fingers and delivers less sound.
A cheap instrument will probably require less work in the first half year (and deliver even less sound), and then you won't even be able to play all frets.
First of all, you shouldn't compare a guitar as cheap or expensive by looking its price or brand while buying a guitar. But these things makes difference :
- The guitar wood : guitar wood material is so important for getting the sound. Good guitars holds resonance and voice of every note, and wood quality is one of them.
- Guitar fretboard : Fretboard wood, thickness it an important criteria for a good guitar. In my opinion, too wide fretboards decreases playability, too thin ones brings sustain problems. It's up to you.
- Manufacture place : I will generalize this matter. Generally, guitars made in Indonesia and China are being categorized as cheap. Of course there are exceptions.
In final, good guitars can last longer, have good sound quality, and good playability.
Try them, play them, and you'll feel the difference. As like i said, brand or price is not a criterion for quality.