Intrinsically there is no difference between a classic guitar and a flamenco guitar. All the basic parts are there and there is no necessary difference in design. Rather than take the classic guitar and describe how the flamenco version differs, I would rather turn this on its head and look at it from a Spanish perspective. In terms of the domestic market, the classic or classical if you prefer, was but a small fraction of production until the international boom in classical guitar in the 50’s. Small family run factories such as Tatay and Julve in Valencia dominated the market (and still do) and produced largely a simple sort of instrument which was indifferent as to musical intention other than it function. Woods were chosen for availability and as often as not walnut or mahogany.

The classic guitar developed from the Torres model and was usually either maple or rosewood because that was what Torres used on the guitars of Tarrega and Llobet, the big stars of the day. The flamenco guitars were either rather large for accompaniment or smaller for solo work. Due to the nature of the music, lighter construction was preferred as that resulted in a generally shorter sustain which suited dance rhythm work. How the instrument strummed was of major importance while the opposite was true for the classic style. The classic was really trying to imitate the piano and in doing so ended up, if all went well, to be more of a miniature orchestra. While a skilled player could coax flamenco from a classic and vice versa, having one that volunteered and abetted the appropriate music was definitely better. In the 1890s the ‘guitarra de tablao’ developed which was about 20mm wider and often a bit longer but on first inspection rather shallower by perhaps 10mm. Typically a 9 fan layout was used. Usually constructed of mahogany, maple or cypress, the idea was to give a full bottom end and directional punch for playing unamplified in flamenco shows of the time.

Looking closer we see that both top and back were arched more radically than the modern guitar. An example in my possession (above) has a top arch of about 8mm (three-eighths of an inch) whereas 3mm or an eighth inch is common today. Thus the depth between the plates in the center was actually pretty much equivalent. These were the archtop jazz guitars of the day, to use that analogy. The smaller guitars could be 40mm narrower and also about 25mm shorter. This was more probably  the more typical dimension and, while the bass was less full, the upper strings and melody lines were better served. This was referred to as a guitarra por adelante (p’alante), out front, as opposed to a guitarra p’atras or backup guitar. The same combination can be seen in the small Mexican requinto guitar which does all the fancy work up high over a standard guitar accompaniment. These guitars with their smaller top areas didn’t require as much arch to stabilize the top and were often made flat or almost so.

By the 1920’s the work of Domingo Esteso and Santos Hernandez had elevated the performance of the size and shape that we now know as standard to such a high level that making it smaller or larger seemed irrelevant. Besides which, the standardization of dimension with the classic had production advantages. Smaller guitars continued to be made but increasingly less so. This is rather unfortunate because there are many endearing qualities to a smaller instrument and many players would be better served, but there is an assumption that bigger is louder and louder is better.

A measuring of top thickness of both forms will not show a marked difference, thus the mass of the top is not a factor. The back is a different matter and a classic can be typically 1500 to 1600 grams whereas a flamenco would be 1100 to 1200. As the rest of the construction is typically the same apart from perhaps another 100 grams for machine tuners in some cases, we can assume that there is another 400 grams in the back and sides. This is very significant considering that the major vibrating area of the top is maybe 100 grams total. My analysis of the radiating patterns of various guitars leads me to a generalization that heavy bodied guitars have more low frequency directionality.

In a typical flamenco setting it is possible to have the guitar near a wall such that the bass is reflected forward regardless of the low mass of the box. This has the advantage of giving a short sustain compatible with rhythm work yet more fullness to the overall sound. The same guitar on a concert stage would be at a comparative disadvantage without a reflective shell at a judicious distance. Thus the ‘concert’ classic guitar is optimized for the element in which it is used as much as for the music. Indeed, many early classics were hardly heavier than their flamenco counterparts with the main difference being subtleties of bracing, action height and golpeadors.

By the 80’s we have many classics in the 1700 gram range and Greg Smallman at 2200. This instrument has a cedar top about half as thick as usual and a lattice bracework of balsa and carbon fiber so the ratio of body to top mass must be quite radical. John Williams used this design extensively and having experienced similar guitars I can vouch for their effectiveness.

The flamenco guitar which weighed about 1200 grams in 1920 still weighs about the same today, give or take the variations in tuners. Some of the soloists have gone to heavier construction for the newer instrumental music but for the traditional song and dance the recipe seems static. Thus, you have a given amount of standard materials, of which there is a minimum to start with, so the variations are in where and how you put it rather than how much. This makes it either simpler or more difficult; it is reasonably straightforward to make a functional instrument – or should be! – but to make a great one requires mastery of all the aspects of the construction and some inspiration as well.