Building your own marimba instrument is an economical alternative to purchasing commercial instruments and offers you an opportunity to expand and perfect your artisan skills.
As it's crucial that the keys be well seasoned and resonant wood, however, if possible use different kinds of timber - even softwoods! - for making an instrument out of wood.
Frame
A marimba's frame is typically composed of hard and strong woods like rosewood or paduk, while alternatives might include babinga (mainga wood) and synthetic materials, though their resonance cannot compare to that of rosewood. When selecting high quality wood for this instrument, quarter sawn and knot free is paramount to achieve optimal sound. Each bar on this Marimba instrument has an individual note and tuning determined by factors like its position on the instrument, its resonator size/shape, thickness of bar itself and distance from center point key- this specification may differ between manufacturers.
Marimba bars are often curved and tapered, and their dimensions don't always remain consistent across an instrument. A standard marimba will have 17 keys with 40cm being its longest bar while any subsequent bars may be shorter by 1 cm each (this varies between manufacturers). Before cutting out templates for cutting bars out it is essential that center lines and node position lines be marked clearly as these marks can easily get obscured when cutting. 22.5% from either end provides for precise tuning for even novice percussionists.
Marimbas are one of the most beloved school percussion instruments. Easy to make and don't require extensive initial technical skill, these beautiful instruments sound incredible from day one and offer incredible versatility - playing almost any tune possible.
Marimbas can be constructed out of inexpensive and readily available timber, unlike many other woodwind instruments. While concert quality instruments often utilize exotic woods like Honduras Rosewood or African Padauk for concert quality sound production, these instruments can still be constructed successfully using ordinary fir or red cedar from your local hardware store or lumber yard, or with climbing rope from your climbing gym - offering good sound at a more reasonable cost!
Keys
Once you've successfully tuned and built a marimba frame, it's time to focus on its keys - the resonators which hold and support its strings running throughout the instrument and between its bars. These instruments are usually constructed out of either rosewood or padauk wood from Africa and Southeast Asia, and typically feature box or pipe resonance for multiple octaves, diatonic, modal or pentatonic scales and keys whose length depends on how many octaves the instrument covers. A five octave instrument often has two longer octaves due to resonation pipes with larger diameters being required in their upper two octaves. Some keys may function without any form of resonance pipe while others have them hanging below to store beaters and allow storing space underneath for the strings.
Crafting keys accurately determines whether they produce high or low tones. Wood has its own natural frequency which determines its pitch; for this reason, to change notes to higher or lower tones, their underside must be sanded differently based on node position lines marked on your template - typically 22.5% from either end of the bar being sanded - thus producing harmonics unique to that bar being sanded.
Once your keys have been sanded and ready to be suspended, it's time to create the resonator pipe. Resonator pipes should be half of wavelength of note produced by key sitting above it - creating an effective closed resonator that increases volume and sustain of any note played.
One method for crafting resonator pipes is using cut down wood piping as the material for their construction, or wooden batons to keep the pieces upright as they're being attached. Once in place, utilizing some form of adhesive should help secure them and ensure their proper operation.
Resonators
Assembling a marimba begins with creating the bars. These may be constructed out of any type of wood - rosewood is popular but padauk from Africa and Southeast Asia can also be used. Each bar should cover at least an octave or less when struck; and must be accurately pitched so as to produce its intended note when struck - typically using a tuner to find out exactly which frequency produces this desired note when struck.
Resonators are tubular structures made of aluminum or brass which have been cut to their proper length and attached to a frame by hooks or posts that wind around them. A cord or thick string passes through holes in each resonator and links up all of its notes in an instrument; using exact length resonators is vital as any deviation could cause tone plates to sound differently or even produce no sound at all.
Tuning machines can also be invaluable tools in building your Marimba; they allow you to check notes for pitch issues. Basic chromatic electronic tuners can often be purchased for under $50, making this an investment that will save time, frustration and money in its construction.
To create keys, a template should first be cut out from well-seasoned and resonant hardwood such as Karagatch (Kawagatch is a type of elm from Central Asia). The longest key measures 5cm across and 2.5cm thick - there are 17 keys in total with each key 1cm shorter until finally there's just 24cm left to go! Additionally, thick card or foam core templates are often used to speed up this process.
There are various alternatives for use as resonators, all designed to sound similar to the timber resonators typically seen on commercial instruments. By following this guide's recommended lengths and frequencies as well as tuning your bars with care and precision like professionals do, your instrument should sound just as great!
Beaters
A marimba may appear to be an inconsequential instrument - just a few planks of wood resting on a frame, with resonating tubes to amplify its sound - but once you experience its expressive power and versatility it becomes evident that this simple instrument can produce such diverse tones and sounds.
To produce all of the different sounds that a marimba can play, it is imperative that it has suitable mallets. Beaters consist of sticks with cores; their material has a major impact on tone production by the marimba; these cores may consist of hard wood like walnut or soft material such as yarn or chord. Furthermore, hard beater tips tend to produce louder contact sounds.
To build your own Marimba, first you will need to source suitable timber. Eucalyptus wood is commonly used, though other hardwoods such as red cedar may also work. When purchasing wood for marimbas it must be well seasoned and resonant as degraded timber can drastically change its sound properties over time, ruining its acoustic qualities and ruining your instrument altogether.
Once you've secured an appropriate timber, you must create the keys for your marimba. A good way of doing so is using templates with center lines and node position marks on them as guides for cutting keys to length before sanding. After finishing up this step, test them by placing the keys on resonator tubes and striking with mallets (or screwdriver handles wrapped in cloth) with mallets - your resonator tubes should resonate and in tune bars should appear on them for testing purposes.
Concert quality marimbas are typically constructed of Honduras Rosewood or African Padouk; however, you can construct one out of any hardwood with careful tuning of its bars and resonators. Acoustic properties of wood will affect sound output - however this can easily be overcome through careful use of tuning devices on bars and resonators.