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Handmade Stringed Instruments for Traditional Music
In this section I have expanded on a few of the methods I use in the construction of your instrument.
Top Design and Bracing
The top or soundboard of an instrument is the part that really has to work. It needs to be able to detect the vibrations from the strings through the saddle and bridge, amplify and project them while imparting its own colour and characteristics and also those of the main body of the instrument.
To design a soundboard for a Bouzouki we have to consider a number of things, primarily though, how do the strings connect to the top. Most bouzoukis have a floating bridge and tailpiece -
The strings on a bouzouki with a tailpiece and floating bridge impart a force pushing down onto the top of the instrument, one of compression, (the strings are trying to force the bridge into the top). It is an entirely different force from the strings on a guitar, which is one of shear, (the strings are trying to pull the bridge off). The bracing pattern for the top should reflect this difference.
The conventional guitar X bracing pattern and its derivatives cope very well with this shear force and have been designed with this in mind. But an X bracing pattern is totally inappropriate where the forces are in compression.
The bracing pattern and top design I use for my instruments is designed to cope with the compression force while still allowing the top to vibrate freely and project. It is based on a Transverse pattern with carefully graduated Assymetrical braces which spread the load evenly while still allowing the top to vibrate and project. The thicknessing and feathering of the top is also critical to achieve the response I am after.
Integral Neck Block and Jig Construction
The way the neck joins the body of an acoustic instrument has a big impact on the tone and sustain. Most instruments will use a conventional dovetail, as in an acoustic guitar, or more commonly these days, a mechanical bolted joint. Both of these methods have a detrimental effect on tone as they can dampen the transfer of vibrations.
I use a variation on the Spanish guitar ‘Slipper Joint’ which uses a one piece integral block as part of the neck construction, ie: the neck and block are carved from one piece of wood. This method of construction has distinct tonal advantages over the more conventional methods doing away with a joint of any type. Another advantage is greatly increased sustain.
There is no stronger way of connecting the neck to the body, however is presents its own difficulties as a different system of jig construction is needed to incorporate the neck.
The system I use overcomes these difficulties, and allows the instrument to be built completely within the jig providing perfect geometry and alignment.
The Back and Sides
I build all of my instruments with ‘live back and sides’. That is to say they play an active and essential role in the overall tonal complexity of the instrument. Also the type of wood used for the back and sides play an important part in the tonal make up of the instrument.
Fully Compensated Bridge
The correct placement of the bridge and the fitting of a fully compensated bridge saddle are essential to produce an instrument which keeps its tuning and intonation all of the way up the neck and also when a player uses a capo. I position a small discreet mark at either end of the bridge so the player knows exactly the correct position of the bridge if it moves out of place when changing the strings.
Top design with Transverse Asymmetrical Bracing
Fully compensated bridge saddle with bridge position markers.