What is a Size 5 Guitar?

Every once in a while we get a vintage Martin guitar that looks like this one:

You’re looking at a 1956 Martin 5-18. This is a size 5, or terz, guitar. It’s one of the smallest guitar sizes C.F. Martin & Co. has made, even smaller than the Little Martin guitars. Traditionally tuned a minor third higher than a standard guitar (G-C-F-Bb-D-G), short scale size 5 guitars were popular in the 19th century. So where does the number 5 come from?

Christian Frederick Martin arrived in the United States in 1833 and soon set up a music shop in New York City. A German immigrant, Martin had apprenticed under celebrated Viennese guitar maker Johann Stauffer at one of Europe’s largest and best-known guitar workshops. In New York, Martin built guitars and sold a variety of musical instruments, sheet music, and other goods, much of it imported from Germany.

Early Martin Guitar

Surviving Martin guitars from this era are much like the guitars that were built in Europe at the time, and they look much different than the Martin guitars that we are familiar with today. His early guitars have almost figure 8 shapes, with upper bouts nearly as large as the lower bouts. Many guitars from this era have elaborate curved headstocks with tuners all on one side, somewhat like the headstocks Leo Fender and Paul Bigsby would design some 200 years later. These guitars also would have been strung with gut strings, as steel and nylon strings wouldn’t become widely available until the 20th century. Internally, Martin’s guitars still used fan bracing, rather than the X bracing that eventually became the industry standard for steel string guitars.

In 1839, Martin sold his musical inventory and moved to Pennsylvania, near Nazareth, where he was able to focus on building guitars. In Martin sales books, sizes were noted by numerals as early as 1852, listing sizes 3, 2-1/2, 2, and 1, with 3 being the smallest and 1 being the largest. Sales ledgers from 1854 show smaller size 5 guitars, as well as larger size 0 guitars, for the first time.

While size 0 (aka single 0) guitars are often referred to as parlor guitars today, that size was considered a full size guitar in the mid-1800s. The size 2, Martin’s best selling model at the time, was a true parlor guitar, marketed primarily to women for entertaining guests.

In the early 1840s, Martin started using X bracing on some guitars. This became a crucial feature when steel strings became popular in the early 20th century, requiring stronger support than fan style bracing could provide. Over the next several decades, C.F. Martin & Co. introduced the now familiar 00 (late 1800s) and 000 (1902) sizes. The dreadnought, Martin’s flagship body size, was first produced for the Oliver Ditson company in 1916 and appeared in Martin catalogs in 1935.

Sizes 1, 2, 2-1/2, and 3 have all but disappeared from Martin’s offerings. Size 5 Martin guitars still pop up occasionally, but with the re-surging popularity of Single 0 and other small body guitars, don’t be surprised if some makers revisit the once popular size 5.


Martin Guitars: A History - Book One by Richard Johnston & Dick Boak, revised and updated from the original by Mike Longworth

Martin Guitars: A Technical Reference - Book Two by Richard Johnston & Dick Boak, revised and updated from the original by Mike Longworth

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