C: The acoustic Guitar
The acoustic guitar.
A brief history lesson:
This is a very brief description; books and websites could be written about the history of the guitar, its builders and developers (and there are). The purpose of this piece is a brief introduction, as an introduction to the description of what makes a guitar a good guitar.
The acoustic guitar as we know it today has been around for almost 200 years.
It originates from the lute and the vihuela, but its history goes back to around 1350 BC.
Stradivarius also built guitars, but they had 10 strings and thus refer more to the lute. The Sabionari is the only remaining playable example.
See: http://www.sabionari.com/
There was actually no standard for guitars. It was a jumble of strings and the tuning order of those strings. Until Antonio de Torres Jurado opened a workshop for guitar building in Seville in 1843. During his life he developed the guitar as we know it today.
He experimented with sound bars and scale length (the length of the string from top nut to bridge). For practical reasons, that scale length ended up at 65 cm. Most current guitars keep this length.
If you look at the shape of old guitars, it is more elongated and narrow. Antonio Torres de Jurado brought the shape to the shape we know today.
For an extensive lecture on the history of Antonio de Torres Jurado see:
Until the end of the 19th century, lutes were especially popular. As the guitar became known and popular, more and more lute builders (luthiers) switched to building guitars.
The guitar has now far surpassed the lute in popularity.
Guitars were originally built by luthiers. These were often one-man businesses with sometimes a few employees. After the Second World War, industrialization increasingly took off. Large companies were founded that produced guitars in series. For example, we know Gibson (USA), Framus (Germany), Musima (East Germany) Egmond (Netherlands) and Eko (Italy).
Japan quickly followed with brands such as Ibanez, Teisco, Morris and countless other brands.
These large companies actually meant the death knell for the small guitar builders.
Some small guitar builders switched to series production, such as Hijos de Vicente Tatay and Juan Cortés (Spain). Sicily also had a lively guitar production. With brands like Silvestri and Carmelo Catania.
Back to what makes a guitar a good guitar.
Like everything in this world, there are many qualities in guitars for sale. From beginner guitars to concert guitars for absolute top guitarists.
What is a good guitar for you?
As described in the introduction, build quality, sound quality and emotional quality are important.
We will first go into more detail about the build quality of acoustic guitars.
It is clear that the whole thing must be properly put together.
Let's start at the top:
The headstock of the guitar:
This is the part where the tuners are attached. There may be slots in it so that the tuning machines can be on the side. The strings must never touch the wood. This affects the lifespan of the tuning machines. They will quickly break if they are loaded incorrectly.
The tuning machines can also be placed like a violin, but then placed crosswise. They are then tapered pieces of wood with a wing for turning by hand, which are inserted through the wood and work on friction.
The shape of the headstock is quite decisive for the recognizability of the builder. In the 1970s, quite a few lawsuits were filed because of Japanese companies that copied the shape of famous guitar manufacturers. (The lawsuit models) Little came of this, but it shows how important it is for guitar builders to be able to make themselves recognizable with the shape of the headstock.
The headstock can be placed in line with the neck, but this results in a guitar that quickly goes out of tune. (There are tricks for this, but I will come back to that when I talk about electric guitars.)
It is better to have the headstock of the guitar tilted back a bit. An angle of 15 degrees is quite common. The tuning will then remain in order better.
The tuning machines:
They must run smoothly and may not move backwards. With older guitars, tuning can sometimes be a bit jerky. Then there is play in the tuners. Sometimes this can be adjusted, often not. And adjusting is a job for specialists; it really comes down to fractions of a millimeter. If the tuners do not function properly, replacing them is often a good solution.
The tuning machines can have different shapes. The oldest known examples are very identical to those of a violin, then there are examples that are mounted on a base plate and that usually hold three tuning machines.
These tuning machines can be mounted from the side so that they stick into the slots in the headstock, or from below so that they stick through the headstock. The precision with which these tuning machines are made and the pitch of the machines largely determine the accuracy of the tuning machines. They range from very simple to very refined and have corresponding price tags.
Some machines have very beautiful engravings or are gold plated. A matter of taste, not necessarily of quality.
There are also separate tuning machines that do not have a base plate. There are then six separate tuning machines present. The quality requirements are no different from the examples described above. These are often found on western guitars and archtops. They protrude from under the headstock to the top.
The nut can also contribute to poor tuning. If the grooves are not properly placed or are worn, the string will not slide through them properly. Sometimes adding a tiny bit of graphite powder helps, sometimes the grooves need to be touched up, and sometimes the nut needs to be replaced entirely.
The neck:
On classical guitars, the top is flat. On archtop guitars and western guitars, it has a radius (curvature). The neck should be straight and not deformed.
If a neck is bent, you can see this from the space the strings have at the 12th fret (the action). If the action is more than 2 to 3 millimeters, the neck is probably bent. Keep in mind that the easiest way to lower the action is to lower the bridge. It is also the worst way. The string should ideally make a 45-degree angle behind the bridge towards the sound box. Then the tension that is delivered to the sound box is optimal and the sound is best transmitted to the sound box. If you lower the bridge, the tension becomes less and that affects the sound quality considerably. See also: the bridge.
There should be no wear spots from playing in the fretboard. Fretboards can be replaced, but this is so expensive that it is only financially feasible in a few cases.
The bottom of the neck always has a certain form of rounding. There are many different shapes of necks in use. From very solid necks to very thin ones. The thickness and shape of the neck is quite decisive for the playing comfort.
The right shape and thickness is different for everyone. Someone with large hands will have a different preference than someone with small hands. So it is not a question of good or bad, it is a question of preference and often also habit.
There is also no one standard for the radius of the neck, but there are various different curvatures. This is also not a matter of good or bad, but personal preference (and habit) also plays a major role.
Necks can be fitted with a truss rod. This is a special metal rod that can be tensioned like a violin bow. This is often used in western guitars and electric guitars. It is rare in classical guitars, but they certainly exist.
The truss rod serves to align the neck under the tension of the strings. This is certainly recommended for metal strings.
The heel:
The heel of the guitar is the piece of wood that connects the neck to the sound box.
This is a very important part for the stability of the connection between these two parts.
If this connection is not done properly (substandard), the neck can come loose from the sound box. If the heel is made too coarsely, the part that protrudes from the sound box will affect the playability of the higher notes of the neck.
The frets.
At first glance, it may seem that a fret is just a fret, but there are also major differences here. The dimensions of frets can vary considerably; both in height and width. In the current trend, we are increasingly seeing Jumbo frets appear. Old guitars often have very narrow and low frets. The types of materials are also quite diverse. From brass in old guitars to stainless steel in modern guitars. The advantage of stainless steel is that it is virtually indestructible. The disadvantage is that it is difficult to work with. Brass is easy to work with, but also wears out more quickly. Nickel-silver alloys or phosphor-bronze alloys are often used.
But no matter what frets are in your guitar: they should not stick out and should be neatly rounded and flattened. In old guitars, the wood dries out a bit and shrinks as a result. The frets do not shrink and can then stick out. That is not really pleasant to play, because your fingers are constantly going along and against them, and that feels very unpleasant. In extreme cases, you can cut your fingers on them.
The frets should also not have any dents from playing. That causes the string to 'clatter' on the next fret. Re-flattening frets is only possible to a very limited extent. Usually, re-fretting your guitar is the best solution.
If frets are not properly flattened, they will touch the next fret, resulting in clattering. NB: First have the position of the neck checked before you start working on the frets. If the position of your neck is not right, you will mess up the frets when you work on them. If you don't know what you are doing: take your guitar to a good luthier. You often ruin more than you do good.
The sound box.
Perhaps the most important part of an acoustic guitar for the sound.
Why is it so important? Simple: this is where the sound is formed. The vibrations caused by the strings are transmitted to the top and amplified by it. The shape and dimensions and materials used for the sound box determine the formation of the sound.
The materials:
The top of a guitar is usually made of pine (spruce). It can also be made of plywood. Plywood is cheaper and easier to work with.
However, guitars with a plywood top can also produce a surprisingly good sound. You can read how this is possible further on.
The top can be flat (just like the bottom) or it can have a curve. Guitars with a curve are called archtop guitars.
You can achieve this curve by either bending the top or by cutting it out (by hand), just like in violin making. These cut out tops are very expensive compared to curved models.
The sides and the bottom can be made of different types of wood than the top. These other materials influence the sound. In flamenco guitars you see light types of wood used to get a short, bright tone. Maple is used in the more budget models, Spanish cypress in the more expensive models. There are also flamenco negro guitars, which have a dark side and bottom. Rosewood is used for this. They have a different sound than flamenco blanca guitars and there is often discussion within the flamenco world whether a flamenco negro is actually a real flamenco guitar.
A romantic guitar often uses darker types of wood to get a fuller and more sultry sound. For example mahogany or cocobolo.
The sound bars:
A guitar can have sound bars in the sound box. These are very important for the sound. It is quite a study to determine and shape the right shape of the sound bars. And then the place where they are, the shape they take and the number are very important.
A guitar does not have to have sound bars. The cheaper guitars usually do not have them.
Western guitars (almost) always have sound bars in a guitar. With classical guitars you will find them with the more expensive models, with archtop guitars it varies greatly.
You can probably imagine that making lead bars for a curved top is much more difficult than for a flat top. After all, it has to fit exactly. A close fit is not going to work.
The shape of the sound box:
You may have noticed that acoustic guitars are not all the same size.
In the late 1800s, many 'parlor' guitars were built. Parlor means living room. They were mostly ladies of the wealthy class who could afford to have a hobby. That hobby could be making music, and that could of course be on an instrument of their choice: piano, harpsichord, violin, lute or guitar were popular. To show off their skills, living room concerts were given.
Since women are usually somewhat smaller in stature than men, the guitars were made somewhat smaller than we now know as the average guitar. The parlor guitar was born.
It is very difficult to get a strong sound from a small sound box (it is possible, by the way). That is why guitars were often made somewhat larger. The western or jumbo guitars were developed to produce a lot of sound. After all: it is easier to get a lot of sound from a large sound box than from a small sound box. Then the shape for a classical guitar, which was originally more almond-shaped and elongated, has become a bit more 'round'. It turns out to be a good shape for a good sound.
The glueing:
Guitars are glued. The quality of the glue is therefore very important.
In the past, bone glue was mainly used for this; glue made from boiled bones. The disadvantage of bone glue is that it loses its strength after about fifty years.
Modern wood glues are stronger than the wood itself, and are permanently good.
So if you buy an old guitar, you should pay attention to the gluing. If there are loose parts visible, the guitar is due for a complete restoration. It must then be completely taken apart and re-glued. This is usually quite expensive. Re-gluing parts is not recommended, because modern glue adheres very well, and if the rest also starts to come loose, you will have a problem taking the guitar apart. So: do it right, or don't do it at all.
The sound holes.
The shape and position of the sound holes are also determined by the sound.
These are often round and are located under the strings just behind the neck leakage.
However, with archtop guitars you see f-holes next to the strings in the bottom of the guitar.
The f-holes also have characteristics, such as cat-eyes or fantasy shapes.
The f-holes are clearly based on the f-holes in violins, basses and cellos.
Nowadays you (also) see openings appear on the visible side of the guitar, positioned so that the guitarist is more in the flow of the sound.
I once had a guitar that I found disappointing when I played. When I sat directly opposite another guitarist who was playing this guitar, the sound actually came through very well (and no, that had nothing to do with my guitarist, joker). The sound was directed enormously forward, which meant that you only heard part of the sound from behind the guitar. I can well imagine the alternative sound holes in the side. The experiment is fun in any case.
There are also very beautiful jigsaw sound holes made. I always find it a pleasure to look at. It has no practical use, but it shows an enormous amount of craftsmanship.
The bridge.
The bridge of the guitar is the part that transmits the vibration to the sound box.
It is held in place exclusively by a glue connection. The glue connection must therefore be very good. With Western guitars you often find two bolts and nuts that help absorb the force of the metal strings.
The bridge consists of a wooden part and a bridge saddle that is made of plastic.
The placement of the bridge is crucial for the correct intonation. If this is even slightly wrong, the intonation will never be correct.
With electric guitars it is often worthwhile to adjust for a pure intonation. With systematic guitars this is the same as a fixed straight line. There is nothing to adjust in itself. However, some bridge saddles have an offset section largely on the b-string or the g-string. There are also fully compensated bridge saddles for sale. This can sometimes help the guitar to get intonation better.
If the neck (due to the excluded pulling of the strings) becomes warped, the owner sometimes reduces the bridge nut so that the action becomes acceptably acceptable again. However, this reduces the tension on the strings on the bridge, which leads to a loss of quality of the sound. It rarely or never leads to a guitar that is easy to play. The neck will simply have to be realigned.
For a western guitar, the truss rod is the best way to do this. Most classical guitars are not equipped with a truss rod because the string tension of nylon strings is much less than that of metal strings. Necks without a truss rod can be aligned, but there are only a select group of luthiers who can do this well.
The label.
The label is usually located in the sound box under the sound hole. The label can contain the name of the builder, the model number of the instrument, a production number, a date and any contact details of the builder. Never remove the label. If it comes loose: carefully stick it back on with a little wallpaper paste. It is the only thing that can identify an acoustic guitar. A guitar without a label is immediately worth much less than the same guitar with a label.
There can also be serial numbers on the inside of the heel.
You can sometimes find a brand name or a serial number on the headstock of an acoustic guitar, but most of the information will always be found on the label. This is different for electric guitars; there is often no sound hole, so the information will have to be applied differently.