If you're like me then you have a healthy interest in various world musics and instruments, which is also part of your attraction to capoeira. The berimbau captivated me right away. It is a simple instrument with a haunting and soulful sound. I instantly knew I had to learn how to make them. And so I set out to do so. I've been making them since I began capoeira in 1997, both for personal use and for sale to capoeiristas and musicians.
Here's a summary of the things I've found important to selecting a good berimbau and caring for it through the years.
Look for: A proper berimbau is about 5 feet in height, plus or minus 3 inches. It should have a gentle even curve from end to end. Avoid any examples where the ends are mostly straight and where it has a sharp bend in the middle. There should be a gradual even taper in thickness, similar to an archer's bow. The wire should be clean and bright. Wire that is very corroded or pitted will likely not hold up very long. The pedra should be of hard solid stone, round and flat, about the size of a silver dollar, and not too thin. Stones that are too thin don't have enough density to stop the sound properly to produce a bright high note.
Look out for:Exposed knots in the middle third of your berimbau have a good likelihood of splitting under high tension. Knots in the upper or lower third are not so much an issue, because there is much less stress in those areas. Deep splits are a sign of poorly cared for or old and weathered wood that probably has a short life ahead. Unsecured leather on top will likely cause you trouble ahead and definitely require repair. The leather top should be securely affixed by both glue and tacks. Overly light weight is a sign of low density, and more likely to break under tension. A berimbau that is too easily strung or overly bendy is a sign of poor spring strength. This is likely to produce an overly low note and diminish quickly in spring power. A berimbau that is too stiff to bend is a sign of improperly made or overly thick wood, and not worth the struggle.
Cabaça:This should be round or oval in shape. Avoid flattened shapes as it makes getting a proper grip difficult. Your cabaca should have a thin, hard wall. A cabaca with a wall that is too thick won't produce good volume. A flat or rounded bottom is important, but should never be concave. Where the cabaca meets the beriba there should be only one point of contact. A sound hole relative to the size of the cabaca, but not too big or small. This should be cut at about the top quarter. Sound holes that are too small can be opened, but overly larges holes are a lost cause. String holes where they attach to the beriba should be equal width or slightly less than the width of the berimbau. These should never be wider. It is important to have a good varnish to protect against moisture and wood destroying insects.
Care:Unstring your berimbau after each use. Your berimbau should not be left strung for more than a day.
Take extra care when stringing, slow and steady, paying careful attention to the range of flex and not going past its limit. Never leave it strung in a hot car or let it be overexposed in the hot sun. This will warp the wood and leave it with less spring. Have a good oil varnish to protect against moisture. This will also prevent splits from developing. Always carry your cabaca in front of you where you can see it, or in a carry bag so it doesn't get knocked around.
A good berimbau that is cared for properly should last many years. Good luck!