A Backpacker Violin

Intro: A Backpacker Violin

Travels are a never ending source of inspiration and most of the times I had to leave my violin at home because it was too complicated to carry such a delicate instrument with me. Finally, I've started creating a robust and modular version of a violin that I could put in a backpack.

More information on this website

The idea started during a travel in Africa while visiting different developing projects in the south of Tanzania. Later on, I've continued to develop the archetyp originally built during this trip, finding a way to amplify it, improve the proportion, keep the tuning...

After many different trials we have developed different models following some basic principles: Dimensions and proportions are the same of a classical violin.

-Violin maintainance is the same (same bridge, keys, strings...)

-The sound is generated from the vibration of wood, skin and metal (and not only from the strings)

-The instrument is modular and robust.

-The handle allows the insertion of different harmonic resonators, shoulder rests and electronic devices.

STEP 1: Inspiration

While creating these violins, we let us get inspired by ethnical and ancient instruments, trying to reproduce similar resonators which can be put on our universal handle.
The instruments that have fascinated us the most are ekhtara, vioara cu goarna, calabasa, viella, and kamancheh.

STEP 2: Building Up

To be able to condense all these principles in one violin we had to go through several trials. Finally we managed to create a good instrument by using the following set of materials:

-sooden stump (mainly from local wood (oak, beech, mahogany) 4x6x30cm around 5-6E

-hollow metal pole 1x40cm 3E/m -Olive, padauk

-4 tuning pin, 10-12E

-string holder 10E

-strings 20E -bridge 5E

-audio cable 1E/m

-jack 2E

-2 piezo, 1E

-2-3 trimmers 110kOhm 3-5E Construction)

-Sanding 3E

-Glue 0.5E

-Varnish 1E

-Concept

We have worked on the simplicity of the form keeping inspiration from simple geometrical forms. 2D and 3D draws are available on the projects section.

STEP 3: Materials and Construction

After many tests we have sorted out the best materials for functionality
and shade combination. Some woods where taken from the territory (olive, waldnut, cherry, castanie). That allowed us to choose the direction of the cut and store the slices of wood in a dry and ventilated warehouse.

-Handle
The handle is built respecting the exact dimensions of an acoustic violin and preserves the same references for the hand. It is usually made of oak, mogan, buche... The top has different forms depending on the kind of resonator it is built for. We particularly like the form of a crown pit. The total length is about 63cm. There is a reference attached to the left side of the handle to counterbalance the shoulder rest on the right side. Fingerboards preserve the original size and are usually made of padauk or olive. Generally we place a diamond shaped wood knot in the middle of the fingerboard. This peculiarity is typical of the olive wood.

-Shoulder rest

The shoulder rest can be embedded between the handle and the string holder. It's a single piece designed to sit on the breast and the shoulder. One can extract it to reduce the lateral size of the violin during the transportation. Shoulder rests are extremely customizabile according to the posture of the violinst. They are designed/dimensioned to balance the total weight of the violin and to shift the center of mass towards the body to release the load on the left arm.

-Resonator

At first, we have tried different kind of resonators made of bamboo segments, coconuts, pumpkins or more complex forms obtained by using wood slices. The most performant resonator was a bamboo segment whose lenght was the half of the total string length. This simple resonator was extremely rich in harmonics, and substain was long lasting. Without amplification the sound is gentle and does not disturb the neighbours. We have tried resonators with parts made of skin, metal, springs, to mechanically elaborate and enrich the sound.

STEP 4: Amplification

-Amplification
We have put two contact microphones (piezoelectric) inside all the resonators we have built. A thin layer of wax filters spurious vibrations. The microphones have different characteristic resonance frequencies, the smaller resonates aroud 2.8kHz and it is closer to the bridge, the larger resonates around 4.6kHz and it is placed further away from the bridge. The short distance between the two microphones introduce a natural reverber and the mix between the two mics construct the characteristic sound of the violin.

-Harmonic analysis

We have analyzed and compared the power spectrum of the sound of the electric and classical violin recording with environmental microphones. We have calculated a time averaged spectrum using baudline. In the picture an A string was played. We can see that the electric violin is rich in harmonics albeit the classic violin is stronger in the low frequency range.

STEP 5: Varnishing

For the varnishing I've experimented different methods to orient around lacques, shine, soaks, dyes, stains, wax, oils... At the end I've decided for: I) sanding 40 II) sanding 180 III) sanding sponge IV) sanding 400 V) oil wiping VI) first pass of transparent shine wiped with a drape VIb) light sanding 400 VII) second pass of shine.

STEP 6: Envelope

The envolope is a simple textil bag with a soft padding, the straps connect the bottom with the closure strip. The violins without shoulder rests are more compact and have no fragile parts.

Comments

[smallly]

I'd like to order one. How much and how long would it take?

[AtahualpaA]

how do you interconnect the 2 piezo?

[tareka2]

This original musical instrument Pharaonic

[cristoph]

What's the 7 shaped piece for looks cool just didn't know if it served a purpose

[viudi]

You need it to find the correct positions with the left hand, otherwise it's really hard to find the right pitch on a violin

[momoluv]

Wowah super cool great job

[viudi]

Thanks, I really like your art apples too

[momoluv]

Thanks so much!

[jtmoffatt2013]

Does the metal pole go all the way through the handle? How does it attach to the resonator? This is a fantastic project, I really like the look of the violins on your website!

[viudi]

Thanks a lot. The pole is just enters a couple of cm, until is stable. Otherwise the instrument gets heavier and unbalanced to the front. The idea comes from the kamancheh, the pressure of the strings holds the resonator and the bridge like in the vioara cu goarna. I'd love to see different violins on the stage, maybe we manage ourself soon to play gigs around.

[Uncle Kudzu]

Beautiful! Makes me wish I could play a violin :)

[viudi]

I love this instrument, I'm happy I can bring it with me now without risks of breaking it. I didn't start as a child, I guess one can always learn.

[Joat-fl]

What is the cost?

[viudi]

I like first to understand what violinists want to play before start designing and building a violin for him/her, we just made an acoustic one too. Personalization is really important. Otherwise self made is not expensive (like in the bill of materials in the instruct) if you already have good dried wood.

[Attmos]

Nice! How does it sound, you know, without a soundboard?

[Attmos]

Sorry, read the whole thing now. It's electric. Are most electric string instruments made like this or do they use pickups like a guitar?

[jtmoffatt2013]

Bowed instruments can't easily use coil pickups like an electric guitar because the strings are all different heights and the vibration is primarily horizontal. The piezo pickup uses the vibration of the body rather than a magnetically induced current like the coil.

[viudi]

Right, that's the idea. I've always hated the sound of pick ups because the mainly capture the movement of the the strings, they are far too dry. I like to mix the vibration of the harmonic resonator with the metal pole and the skin. Piezos in different positions improve the timber of the sound capturing different vibrations.

[Attmos]

Very interesting, I didn't know that. Thanks for all of this information. I don't play... any musical instrument, just drums, but I've always admired the craftsmanship that goes into making any and all stringed instruments.