There are several different body styles of acoustic guitars out there. Here we will be talking about the most common 5: Dreadnought, Grand Auditorium, Orchestra or Auditorium, Grand Concert, and Parlor Guitars.
Investigating the differences in Size & Sound we will use this knowledge to pair the right guitar to you and your needs as a guitarist:
These guitars were created to be the workhorse for flat picking and large strumming guitarists. If your focus is on big chords with a big sound, this is for you. Well renowned for its rich low end and balanced EQ range, this guitar will have the greatest projection of the (5). The Dreadnought has an overall rich, warm, and deep sound to it.
Grand Auditorium guitars sit right on the line between Chordal playing and Finger Picking. With a slightly reduced body size, this guitar looses some of its rich low end but compensates with a rising mid frequency range. Size-wise, this is your Goldilocks Guitar if the dreadnought is just a bit too bulky for you.
ORCHESTRA -or- AUDITORIUM
Slimmer and curvier, Orchestral Guitars make it easy to wrap your arms around. Very mid-range heavy, this guitar is sought after for Singer-Songwriters and Finger Pickers. This is the brightest sounding guitar before we start noticing a significant reduction in the depth of sound.
For guitarists that have small hands and are finding "normal" guitars to be too strenuous on their fingers, Grand Concert guitars are made for you. With a thinner body, these guitars may be more manageable, but come at a price of a lesser sound projection. Grand Concert guitars will be the Brightest of all the guitars so far.
These are the smallest of the bunch and may be mistaken for 3/4 or 1/2 sized guitars. THEY ARE NOT!! Parlor guitars have a smaller body, BUT a full size neck. For adults that find the bodies too cumbersome but are in need of full-sized guitar neck, these are your ideal guitars. Adopted by many blues players for their punchy mid-range and gritty sound. Whether you are in the market for learning Slide Guitar or a guitar that takes up minimal space for your Dorm Room, this is a great option to consider.
Different manufactures of the same shape will provide different Feels, Sound Quality, and Guitar EQ.
Physically play on different models or ask someone to play for you, LISTEN!
No two guitars play the same, so test them out and Olivander's those guitars until you find the one made for you.
PRICE DOES NOT ALWAYS REFLECT QUALITY.
With a grain of salt: Most Beginner Guitars below $100 (just for the guitar itself) suffer in hardware - tuners don't lock in strings, pieces break off, "fighting to play the instrument" - unless it's a House brand where they can cut a good deal.
For a LASTING guitar, I would recommend not looking below $200 for the same reasons above.
Be wise, this is an investment! Do your research and investigate reviews.