Some players think acoustic guitars are simple things compared to their control-laden, pickup-loaded, electric brethren. Not so. Tonewoods, bracing and shape and size are all key to how your acoustic will sound and feel, relying on guitar-making craft going back hundreds of years.

Sizes and shapes of acoustic guitars have changed a lot over the years, so here’s a quick guide to what you might expect. Variations of acoustic size and shapes mean that two guitars with bodies of roughly the same size can often sound very different from one another.

As always, try before you buy. Here are just a few options. Which do you prefer?

“Parlor”-size Gibsons

The earliest Gibson acoustics of note were in the L-series. These are small-bodied, usually around 13.5 inches across the lower bouts. A classic example is the Gibson L-1, produced between 1902 and 1926 (as an archtop) and 1926 and 1937 (as a flat-top). Robert Johnson is famously associated with the L-1 – that’s what he’s playing in the portrait of him in a suit.

Robert Johnson

But a bona fide L-1 would have been expensive for a traveling bluesman such as Johnson, so some blues historians suggest this guitar may have been borrowed. It could well be that his more regular gigging L-size was a Kalamazoo model KG-14 (see in Johnson’s “cigarette” portrait). Kalamazoo guitars were a value brand offered by Gibson during the depression era. The KG-14 originally sold for $12.50.

Guitars of such sizes are often referred to as “parlor” guitars, as they were only designed for playing small rooms. They tend to be defined by a brightness of tone, yet can often offer surprising volume for such small guitars.

“Parlor” guitars – Gibson simply call them “Small Body” – initially faded from popularity in the 1950s, but have since made a comeback via artists such as the superb Keb Mo’ and his Bluesmaster. Gibson also produce a faithful Robert Johnson L-1. Watch Keb Mo’ describe better than words can.


“Dreadnought” (sometimes Dreadnaught) sizes became more popular between WWI and WWII. The term was popularized by Martin guitars, and named after the hulking British battleship of the First World War. Dreadnoughts are typically be 15''-16” across lower bouts, though you should realize there is little standardization of sizes between various makers - a Gibson “Jumbo,” for example, is circa 16'' across the bouts so there is not a huge difference, sometimes barely any.

Some Gibsons typically referred to as “Dreadnoughts” are the Gibson Hummingbird (from 1960) and the Dove (1962) and Country Western models. The difference? These have square shoulders, unlike most Gibson Jumbos, and are slightly bigger at 16.25”-inches.

Hummingbirds, Doves and Country Westerns don’t look typically “Gibson” to some, but are still coveted for their rich tone and good projection. The Gibson Sheryl Crow model is a hybrid of Hummingbird and Country Western models.

Sheryl Crow Signature Acoustic

Gibson Jumbos

Gibson's first jumbo-sized guitar was the 16-inch HG-24 (1929). But the launch of the Jumbo name came with the Gibson Jumbo Flat-top of 1934. Gibson’s design set the guitars apart – other Dreadnoughts sometimes offered boomy bass and biting treble (1930s “scooped mids”, anyone?. Gibson Jumbos tended to sound more balanced, if some said they were not normally as loud.

As for models, there are many. Gibson J-35, J-45 and J-50s are technically Jumbos (the clue is in the name!) Yet Gibson’s J-45 now commonly referred to as a “round shoulder”. Terms change, but “round shoulder” Gibsons are essentially Dreadnought-size with curvier upper bouts.

Again, Gibson “round shoulder” Jumbos are typically 16-inches wide across the lower bouts but with more sloping shoulders than an original Dreadnought style. It makes the guitar more comfortable to many, but still provides full, rich tones

The Gibson J-45 (introduced in 1942) remains an acoustic classic. It wasn’t a fancy or expensive guitar at the time, as WWII meant guitar building was not a top priority use of grade-A timber. Indeed, Sunburst was initially the only finish available for the J-45, as a sunburst finish can hide wood flaws if need be. A blonde version was introduced in 1947, and called the J-50.

Whatever the finish, the J-45/J-50 design captured magic – playability, and warm and fat tones across the spectrum, but without too much boom that some people find with a squarer-shoulder Dreadnought-style.

J-45s/J-50s are archetypal “singer-songwriter” guitars – good for well-projected strumming, but also with the finesse for fingerpicking. But, of course, it depends on the player’s style.

Super Jumbo size

The Big Daddy! Gibson designed the Super Jumbo 200 in 1937. With a 17" lower bout, these are big boxes. And they do sound different to a regular Jumbo. SJs are extremely well-balanced, loud and clear – they make exceptional rhythm guitars but excel for fingerstyle as well. Did we mention loud? The legendary Rev. Gary Davis said that he played a J-200 so they could still hear him at the back of his packed church. Hear Gary Davis’s masterful “Death Don’t Have no Mercy” on a J-200.

The SJ-200 (from 1937) has become known as “King of the Flat-tops” and is another classic Gibson design. The SJ-200 measures a full 17-inches across the lower bout, and as a consequence produces more volume than a regular-sized “dreadnought.”

The guitar is now referred as simply the J-200, but it is “super jumbo” size – bigger than a J-45 or J-50.

If you are a Who fan, note that a J-200 is Pete Townshend’s bedrock acoustic. He wrote “Pinball Wizard” on his J-200, which starred on The Who’s classic Tommy album. “I picked it out from about five at Manny’s in New York in 1968,” Townshend told “It had a crisp sound and an easy neck. The body shape, the necks and the sheer strength of the guitar are all very important to me. They also look utterly beautiful.”

That big guitar on the cover of Bob Dylan’s Nashville Skyline? It’s a J-200 given to him by The Beatles’ George Harrison.

The sheer size of the J-200 can be intimidating for some players. But another J-200 devotee, Emmylou Harris, is a petite 5’5” and it didn’t bother her. That said, you can now buy an L-200 Emmylou Harris – smaller and shallower, but with the same curvaceous lines.

Emmylou Harris Signature Acoustic

The melding of shape and size maybe began with the J-180/J-185. These have the Super Jumbo styling but – like Emmylou’s L-200 – with a slightly-reduced width across the body – more like a “dreadnought.” The Billie Joe Armstrong J-180 is the latest twist.

What’s your size?
The difference between 13.5 and 17-inches body width is big in acoustic guitar terms. If you think of your acoustic’s body as an amplifier – and that’s what it is – there is more choice than you’d normally find with combo speakers, so choose wisely.

Some players may find a “parlor” size lacks their desired projection. Others think a Super Jumbo is too boomy. Solution? Use your ears.

Which Gibson acoustic is your favorite? Start searching.