Terminologie description du son des guitares (anglais)

Poser ici toutes vos questions techniques, de lutherie...

Modérateurs : Benoit de Bretagne, carlos, chloé

Benja23
Messages : 514
Inscription : mar. 30 mai 2006, 10:27

Terminologie description du son des guitares (anglais)

Message par Benja23 »

Luthiers secrets

How Do You Describe the Sound of a Guitar?
This is very difficult, and is the reason I always try to have a potential customer try one of my guitars before they buy one (but of course, I don't insist!). I don't feel that words are very accurate in describing the the tonal "signature" of any guitar. wood, size and shape, the type and gauge of strings, to name a few. The sound qualities of a guitar are much harder to discern and evaluate. In order to accurately describe the characteristics of a guitars sound, you must first be familiar with the nomenclature used to explain the sound qualities of a guitar. An acoustic guitar's sound has many facets. Here is a brief overview of the terminology most often used when discussing a guitar's sound. These explanations are for the most part paraphrasing of the descriptions given by Larry Sandberg in his (must-have) book, "The Acoustic Guitar Guide".

Tone
When you set a string into motion, the string has a fundamental vibration, as well as many smaller vibrations, called overtones. Most guitars share some fundamental tones and overtones. But they each have their own unique combination of fundamental and overtones also. That's what makes guitars sound unique. The woods used for the back and sides of the guitar factor most into the characteristic tone of a guitar.
• Rosewood gives a soulful, darker sound.
• Mahogany is sweeter and softer, as well as rounder and nicely balanced.
• Maple is louder, like rosewood, but has less bass resonance and a more brittle tone.

Volume
Volume is how loud your guitar is. But not just as measured by a decibel meter, but also how loud your guitar "seems". This is directly related to the quality of the top wood and the construction, the top bracing, and the rigidity of the back and sides. Vibration of the soundboard is the secret caused by:
• Heavier strings
• Specific top-woods, like Adirondack spruce
• Scalloped bracing
Of course the size of the body also contributes to the volume, the bigger body, the bigger soundboard.

Presence
Presence is a psychological factor that is very subjective. It is a gauge of how full your guitars sound is. A good measure of presence is how satisfying your guitar sounds when you play it softly. A strong presence means that the tone quality does not deteriorate with less volume. The efficiency of the guitars top plays a large part in the perceived presence.

Balance
Balance is the relationship between the high and low notes in point of fullness and volume. In a balanced guitar, the notes have equal authority throughout the entire range of the instrument. Guitars that are over-balanced toward the bass are called boomy. Flatpickers and folk singers prefer this type of balance. Fingerstyle guitarists might prefer a guitar that is balanced toward the high strings. Balance is usually directly related to the size of the guitar. Balance is also affected by the body woods (Rosewood is boomier than Mahogany and Koa is most balanced to the mids). The size of the soundhole affects the balance (a larger soundhole usually balances the guitar toward the high strings).

Separation
Separation is the ability of an instrument to express simultaneously played notes so that they are perceived distinctly and individually, rather than as a homogeneous whole. In other words, when you strum an open E chord, is what you hear more like one glob of sound or six separate ingredients? An analogy might be to the flavors that make up a fine sauce. Separation is related to the quality of the guitar, as well as the player's individual touch.

Sustain
Sustain is the measure of how long a note keeps sounding after you initiate it. If the sound decays too fast, you have poor sustain. Sustain is directly related to the quality of the guitar. More specifically, it is the vibration of the top that gives you an honest, clean sustain that preserves all the components of the tone throughout its duration.

Tonewoods
The type of wood used on a guitar is probably the single most influential factor to its tone. There are a variety of different woods to choose from. Below are many different wood descriptions and their general tonal properties. These descriptions are from a Martin Brochure on Tonewoods.

Back and Sides
Brazilian Rosewood
(Dalbergia Nigra) Brazil. Sometimes referred to as "Jacaranda", this species of genuine rosewood ranges in color from dark brown to violet with spidery black streaks. The smell is like roses when freshly cut. Brazilian rosewood is considered nearly extinct and is extremely expensive if available at all. Extremely resonant producing full, deep basses and brilliant trebles. Brazilian rosewood is occasionally available in very limited quantities for custom or special limited edition orders only.
East Indian Rosewood
(Dalbergia Latifolia) India. Typically richly grained with dark purple, red, and brown color, East Indian rosewood is resinous, stable and generally more consistent than most other rosewood species. East Indian rosewood is extremely resonant producing a deep warm projective bass response that is especially accentuated on large bodies guitars.
Genuine Mahogany
(Swietenia Macrophylla) Brazil. Yellowish brown to reddish brown in color, Genuine or "Amazon" mahogany is exceptionally stable and consistently clear. Mahogany is much lighter in weight than rosewood, koa, or maple. In spite of its weight, mahogany yields a surprisingly strong loud sound with an emphasis on clear bright trebles.
Figured Mahogany
This beautiful and rare (often quilted) variety of genuine mahogany occurs in a very small percentage of mahogany trees. Though difficult to bend, figured mahogany shares the same tonal properties of the unfigured mahogany.
European Flamed Maple
(Acer Campestre) Germany. Curly, flamed, tiger striped, or "Fiddleback" maple refers to the characteristic alternating hard and soft rippling which runs perpendicular to the grain in some rarer maple trees. This particular species of European maple is very hard and reflective, producing a loud powerful projective sound. Uniquely figured domestic "Birdseye" maple, used on the D-60 models, displays characteristics and tonal properties similar to European Flamed maple.
Koa
(Acacia Koa) Hawaii. Golden brown color with dark streaks and a lustrous sheen. Koa wood occasionally develops a curly or flamed figure. Regardless of any figuring, koa seems to have a bass response that is slightly less than that of rosewood and treble response that is slightly less than that of mahogany. The result is a very equally balanced instrument.
Walnut
A great selection with bright woodiness of mahogany when played lightly, with much of the punchiness and power of rosewood when you dig in. When properly braced, a walnut backed guitar can have a unique warmth and tonal depth. This is a dark brown, highly figured specialty wood which is grown in a wide variety of locations.
Morado
(Machaerium Scleroxylon) Bolivia. Also known as Bolivian or Santos "rosewood", morado ranges in color from a light violet brown to reddish brown with occasional olive and black streaks. Finer in texture than most rosewoods, morado is a close visual substitute for East Indian rosewood, and has very similar tonal properties.
Myrtlewood
The best way to describe Myrtlewood is that it has the powerful voice of rosewood coupled with all the clarity, brightness and balance of maple. Myrtlewood can be found in the coastal mountain regions of northern California and southern Oregon. With coloration anywhere from an elegant whitish/straight grained look (a blonde mahogany), to yellow/green with flame, the tonal personality of Myrtlewood is consistent. Use of this wood on a guitar was first done by Breedlove and is featured on the Breedlove "Northwest" guitar. Prior to this, using Myrtlewood to build a guitar has never been done.
Striped Ebony
Deeper and richer sounding than East Indian Rosewood, many would characterize striped ebony as very similar to Brazilian rosewood. It is dense, has similar reflective properties to Brazilian, and it also has a high specific gravity. It has a striking, distinctive vertical stripe pattern, variegated dark brown, black and green. It makes a truly exceptional twelve-string. Striped ebony comes from New Guinea, is exclusively government controlled, and is not an endangered species.
Cherry
With a density and reflectivity approaching that of maple, cherry produces a rich, projective midrange and balance without favoring the bass or treble frequencies.
White Ash
White ash was utilized on a limited but extremely popular run of D-16A Martin guitars made between 1987 and 1990. The tonal character of ash issurprisingly loud and bright, with a strong midrange and a crisp bass.

Topwoods (Soundboard)
Sitka Spruce
(Picea Sitchensis) Canadian Northwest & Alaska. Sitka spruce is the primary topwood for Martin Guitars. It is chosen because of it's consistent quality as well as it's straight uniform grain, longevity, and tensile strength. Tonally, Sitka spruce is extremely vibrant providing an ideal "diaphragm" for transmission of sound on any size and style of stringed instrument.
Bear Claw Sitka Spruce
A specifically named variety of Sitka Spruce. A randomly figured Sitka, due to genetic or environmental factors. It looks like a bear has clawed across the grain of the wood. This particular variety is highly coveted for it's unique patterns. From the Pacific Northwest.
Englemann Spruce
(Picea Engelmannii) United States. Englemann spruce is prized for its similarity in color to European (German) White spruce as well as its extreme lightness in weight which seems to produce a slightly louder and more projective or "open" sound than Sitka spruce. Englemann spruce grows in the alpine elevations of the American Rocky Mountains and the Pacific Cascades. It is considerably more limited in supply than Sitka spruce.
Adirondack (Red) Spruce
This legendary wood that Martin used for its tops throughout its golden years came from the East Coast, from the Southern Mountains into New England and upper New York State. Called both Appalachian and Adirondack spruce, it has a creamy white color. Similar to Sitka, Adirondack responds well to either a light or firm touch. It has more overall resonance than Sitka. Interesting grain color variations make this another visually desirable top. Adirondack has been unavailable since the mid-1940's. Virgin growth has been (fortunately) preserved in National parks, the rest is all second growth, plentiful but too small to be usable for guitar tops until recently. Guitar makers have started finding second growth of at least 100 years old that is big enough to be used for tops again. Adirondack is like Alpine spruce expensive.
German Spruce
The "ringiest" of all spruce species. Extremely clear and bell like, with the versatility of Sitka. Exceptional sound for light to very firm techniques. Very white in color.
Western Red Cedar
(Thuja Plicata) United States, particularly the Pacific Northwest. Western Red Cedar has long been utilized as a soundboard material by classical guitar makers for its vibrance and clarity of sound. It is extremely light in weight compared to spruce and the tonal result is generally a slightly louder, more open response. Balanced, warm and rich with bright trebles. What is most characteristic of Red Cedar is that it sounds broken-in, even when new. Exceptional sound for light to very firm techniques. Coloration runs from light (almost as light as Sitka) to a very dark reddish-brown.
Redwood
A great choice for the fingerstylist with somewhat more richness in the bass than cedar. Redwood responds to subtle playing with a crisp balanced sound. The bass response is particularly round and full with a
piano-like crispness. Lacquer and glue do not bond quite as well as the spruces. Because of this (as with Cedar), some Luthiers (Goodall) recommend light gauge strings only on guitars with these tops. Originally from Northern California, many luthiers (i.e. Breedlove) get redwood from recycled lumber and timber salvage.
Western Larch
(Larix Occidentalis) United States. Western larch has clearly marked annual rings and a fine uniform texture. Larch is harder and stronger than most conifers including spruce. It bears a close visual resemblance to Sitka spruce and due to its increased stiffness, it is an appropriate choice for scalloped braced models yielding a projective and crisp response.
Koa
(Acacia Koa) Hawaii. Historically, koa tops have appeared primarily on small bodied 0 & 00 size Hawaiian guitars and ukuleles although recent koa Dreadnoughts and custom guitars have been popular. Koa produces a predominately bright treble response with less volume than spruce, but the slight loss in volume is overshadowed by the extreme beauty of the grain. Koa tops are available on special order and custom instruments.
Genuine Mahogany
(Swietenia Macrophylla) Brazil. Mahogany was first introduced as a topwood in 1922 on the lesser expensive Style 17 guitars. Tonally, mahogany is less projective than spruce, producing a subdued response that is crisp and delicate with emphasis on the midrange. Mahogany tops are usually available only custom instruments, but has recently become a standard top in the Baby Taylor travel guitars.
Walnut
Using a highly figured walnut for a top wood, matched with walnut back & sides, was a first of the Breedlove company but is now offered by Taylor guitars and others. Rich and warm bass with plenty of crispness on the mid and treble side is typical of an all-walnut guitar. Walnut offers a lot of value for your dollar; with the beauty and visual impact of an all Koa guitar, but at a much lower price. Coloration is dark brown with a lot of figure and flame.

Benja
Avatar de l’utilisateur
Benoit de Bretagne
Messages : 13459
Inscription : lun. 03 avr. 2006, 18:49
Localisation : Bernieulles Pas de Calais
Contact :

Message par Benoit de Bretagne »

Et bien dis donc Benja... tu n'arrêtes pas en ce moment! merci pour ces "longs" post... je dois les lire en plusieurs fois... mais c'est très intéressant!!! continue!!! merci :wink: !!!

Benoit de Bretagne
Benja23
Messages : 514
Inscription : mar. 30 mai 2006, 10:27

Message par Benja23 »

En ce moment, je suis en train de lire les newsletter de G Gruhn sur son site. C'est passionnant, car il a vécu le début de l'intérêt pour les guitares vintage, il a été un des premiers à acheter des vieux instruments alors que très peu de gens s'y intéressaient à l'époque. Je vais essayer prochainement de traduire une de ses lettres en français pour que tout le monde puisse en profiter.

Benja
Avatar de l’utilisateur
Benoit de Bretagne
Messages : 13459
Inscription : lun. 03 avr. 2006, 18:49
Localisation : Bernieulles Pas de Calais
Contact :

Message par Benoit de Bretagne »

c'est quelque part un livre d'histoire vivant et ouvert :wink: !?

Benoit de Bretagne
Répondre