Photographer's Note

Good morning everyone, today is my 100th post, I know it's not a milestone here on TE, but just the same, I feel good about it.

Today I'd like to dedicate today's photo to Lisa (delpeoples), who requested a close-up of the bluegrass resonator. She is right about the cool look of the reflections and it also gives you a better look at the face workings of the beautiful guitar. Thanks for the suggestion Lisa!!

Have a great and wonderful Wednesday everyone.....Buddy

Below is some information on the Bluegrass Resonator Guitar.

The Strings:
Like any instrument, the guitar produces sound from vibrations. Just like wind instruments vibrate from air blown through them, guitars vibrate because of taught strings that are plucked by the player. The strings transfer vibration to the wood of the instrument, which projects the vibration as sound. The strings are made of metal, usual steel with a small coil of nickle or bronze wrapped rightly around the four bass strings. (There are normally only three wrapped strings on an electric guitar.) The thin strands of metal are stretched tightly across the guitar neck and supported by a piece of bone or plastic on the neck called the nut, and by a bone or metal piece on the body of the guitar called the bridge. These pieces prevent the strings from vibrating except in the distance between the nut and bridge, allowing the strings to be precisely tuned.

The Body:
When the strings are plucked, they vibrate along their entire length in a certain frequency--the pattern of vibration that produces a musical note. But the sound produced by the strings alone is not loud enough to be heard among other instruments, so the guitar body amplifies the sound. The body of an acoustic guitar is made of up to six pieces of wood that make a box shaped like a gourd. The wood pieces are very thin and usually made of a soft coniferous wood like spruce or cedar, though many employ mahogany and other tropical woods. The thin pieces pick up vibrations very easily, and the box shape lets the wood transfer the vibrations to air inside the guitar, creating sound. The vibrating air is then forced out of a hole in the top of the body, and the sound is amplified outside of the guitar.

Making Musical Notes:
The strings are able to be tuned to certain notes because of their limited length, so all that is needed to make different notes is to change the length of vibrating string. The guitar uses frets, thin pieces of metal attached the the guitar neck, to limit string vibrations. When a player pushes a string down just behind a fret, the metal stops the string from vibrating behind it, changing the frequency and the musical note produced. Very exact calculations and measurements are needed to arrange the frets, since very slight maladjustment can cause the guitar to play out of tune. When made correctly, however, frets allow any note to be played in any combination.

Read more: How Does a Guitar Work? |

What is a Dobro or Resonator slide guitar?

The Dobro or Resonator guitar;
Is a guitar familiar to many as the lap steel sounding instrument on a lot blues, bluegrass and folk music.
It is usually metal or wooden bodied and has a metal cone within it that looks and acts like a speaker.
It can be played either flat or as a regular guitar. Resonators have round or square necks. The square necked types are nearly always played on the guitarists lap.

The player uses a slide or bar made of glass or metal to create a glissando sound. The Slide is used without pressure on the strings.

Resonator guitars are made in other formats including bass and electric guitars as well as versions of Dobro banjo and Dobro mandolin.

Development of the acoustic resonator Guitar;
The resonator guitar is a modern icon. (Most noticeably on the cover of brothers in arms album by dire straits). It has been made over the years in brass, nickel-silver or steel as well as wood.
The original purpose of the Dobro guitar was to produce a very loud sound to compete with the other instruments. Imagine trying to busk in a busy market place or compete with a band to be heard. Before the electric guitar this is what you looked for.
Although it was superseded by the new Les Paul electric guitar and the amplification used for it, the resonator guitar survived because of its distinctive sound.

When was the Dobro guitar invented?
There are three principal types of resonator guitars and they were invented by the Slovak - American John Dopyera (1893-1988) for the National and Dobro companies. (Dopyera Brothers)
The name Dobro comes from the Do of Dopyera and the Bro of Dopyers brothers
The Dobro guitars were first patented on June 29th 1929. The sound of the resonator guitar is produced by one or more aluminum resonator cones mounted in the middle of the top. The physical principle of the guitar is therefore similar to the loudspeaker. The original Dobro had a single cone.

The name Dobro is now owned by Gibson who markets the Dobro brand and the epiphone models which has a range of resonator models. This type of guitar has also been made by other companies including Fender, Vintage, Ibanez, Johnson and National.

How does a Dobro Resonator work - the biscuit, the single cone and the tricone
Resonator guitars may have either one or three resonator cones.
The method of transmitting sound resonance to the cone is either by a Spider or biscuit Bridge. These bridges are an intrinsic part of the resonators sound.

What is a Spider or Biscuit Bridge?
A biscuit bridge is made of a small piece of hardwood placed at the vertex of the cone. This is typical of a National guitar.

A spider" bridge is made of metal and mounted around the rim of the (inverted) single cone. This is a typical Dobro design.

The sound of the resonator guitar is produced by one or more aluminum resonator cones mounted in the middle of the top.

The physical principle of the guitar is therefore similar to the loudspeaker.

The Tricone uses 3 cones with a bridge that rests on all three at the same time.

Notes on playing styles:
Resonator guitars may be played in the traditional position or flat on the lap. They usually have 6 strings although many variations have been built since from 4 string to 6, 8, and 12 string models.
The resonator or Dobro guitars are usually tuned differently to standard guitar tunings including tunings in the key of A, G and D. This allows the use of a slide or bar to play in tune on any fret by covering all the strings. (more on this later ).
The gauge of strings is dependent on the player’s style. They are nearly always metal and may be played with finger picks, the fingers or a plectrum. This choice is again up to the player.

The choice of strings depends also on the neck of the guitar the square necked resonators are better suited to very heavy strings.

More information can be found at the following website:

Photo Information
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Additional Photos by Buddy Denmark (PecoBud) Gold Star Critiquer/Gold Note Writer [C: 408 W: 0 N: 912] (3824)
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