The Resonator (or Dobro) Guitar: An Introduction

Everyone has their own associations upon hearing the sound of a certain instrument. Without doubt, most of us will link the sound of a resonator guitar (also known as a dobro) with the rocky landscapes of the American South – the place where the resonator guitar found its home in bluegrass, country, blues and other styles characterised by the authentic sound of this steel-stringed instrument.

Photos by Gerard Burgers

• Signature Sound
• Dobro
• The Resonator
• Round Neck and Square Neck
• Tunings
• Essential Watching
•     Resonate: A Guitar Story
• See Also

Signature Sound

The resonator guitar is an acoustic guitar that owes its signature sound to a built-in resonator cone. Available in various forms, resonators are mostly used in bluegrass, blues and country, and are also known as Dobro guitars after the brand that made them famous. They’re made either entirely out of metal or out of a combination of wood and metal, and it’s worth noting that some are held and played the same way as an acoustic guitar while others are designed to sit in the lap (lap-steels). That said, what all resonators have in common is that every model has one or more internal cones (see photo below). These cones help to increase the volume and are linked to the strings via the bridge. Whenever the strings are played, the cone resonates along for an amplifying effect that’s more intense depending on the metal-to-wood ratio of the build. An invention of the 1920s, the resonator guitar stems from a time when guitars were still purely acoustic and struggled to keep up with wind instruments and banjos in terms of volume. And even though they were designed to cut right through to the sonic clutter of ensembles, resonators lost their place when the first electric guitars were released. Fortunately, that much-loved resonator-sound had already rooted itself in styles like blues by then.

Dobro

Resonators are made by various makers and come in various shapes and sizes. They’re generically trademarked as dobro guitars – after the brand that pushed the instrument to prominence. The original model was developed by Slovakia-born American, John Dopyera during the late 1920s, following a request from steel guitarist George Beauchamp who wanted a guitar that packed more volume. In 1927, Dopyera and Beauchamp founded a company and brand called National, which is actually still around these days. A year after its founding however, Dopyera left the company and started the original Dobro factory with his brothers (in Slovakian, ‘dobro’ means something like benevolence). Since 1993, the Dobro brand has been in the hands of Gibson who still craft authentic Dobro resonators today.

Tricone model

The Resonator

When it comes to cones, resonator guitars can be divided into three categories: tricone, single-cone (‘biscuit) and inverted single-cone (‘spider bridge’) models. Long ago, things started with the tricone, which was developed by John Dopyera and first released under the National name. Tricone models feature three interlinked resonators which sit underneath the top and have been linked to the bridge which supports the strings. As you can tell by the pictures, resonators are usually made of aluminium. Soon after John Dopyera founded Dobro, he developed another type of resonator: the single cone resonator – the cone of which is connected to the bridge via a kind of spider web-style construction. National responded by coming up with their single resonator: the ‘biscuit’. This model was designed by John Dopyera before he left National and features a wooden ‘biscuit’ with the bridge mounted on top. This biscuit is connected to a resonator which projects the sound towards the back of the instruments. Also, while single-cone models are often referred to as ‘style 1’ resonators and tricone resonators are generally called ‘style 0’, bear in mind that this terminology isn’t always used as consistently.

Spider model

Biscuit model

Round Neck and Square Neck

The various resonators alone have already resulted in a wide variety of available resonator guitars, and this gets even worse when we add the distinction between round-neck and square-neck models. Round-neck resonator guitars are typically played like a standard acoustic guitar and held the same way, while square-neck resonator guitars obviously have a thicker neck and are held and played in the lap like a lap-steel guitar. The strings of a square-neck also have a much higher action, which is to say the strings sit so far away from the fretboard that they can only be played with a slide. And then there are resonator guitars that have been made entirely out of metal, or part-metal-part-wood. These, too, boast unique sonic qualities and add another step to the decision-making process that comes with picking out a dobro guitar. Then again, this is the case with most instruments, and guitars especially. Either way, it’s worth noting that tricones have a slightly milder, more transparent and lilting sound whereas single-cone resonators have that sharper sound that most people associate with the dobro. Meanwhile, dobros built using wood naturally sound warmer and woodier depending on the wood-to-metal ratio.

Tunings

Since a resonator guitar can be played like a normal guitar, it can be tuned to the standard E-A-D-G-B-E tuning. That said, most players will drop their resonator into an open tuning to accommodate slide as well as finger-style techniques, where the open G (D-G-D-G-B-D) and open D (D-A-D-F#-A-D) tunings are the most popular, and where open-D sounds a little chirpier than open-G. The great thing about playing slide guitar is the unmatched amount of subtlety you get to add to gliding notes and vibratos, so if you’re already excited about giving the resonator guitar a punt following this humble introduction, we can only encourage you to keep browsing the internet to learn and hear some more.

Glass slide (left) and metal slide (right)

See Also

» Round-Neck Resonator Guitars
» Square-Neck Resonator Guitars
» All Resonator Guitars
» Lap Steel Guitars
» Slides
» All Guitars & Accessories

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