Online Workshop: Sound Waves
The idea for the workshop was born while researching topics for the summer camps (Yes, we do hope we are again able to organise our very own and very special summer camps — meanwhile here are the videos from last time). Somehow the sound related topics got stuck in our head and after seeing this in the internet, we knew we have the materials in place and it is well suited for our hybrid “pickup plus online assembly” event.
What musical instrument is it?
It is a musical instrument, it is a string instrument! You can not see strings can you? When someone mentions a string instrument one obviously thinks of a guitar, violin or alike. Actually string instruments can be different, the common working principle is that the sound is created by a string that is under a tension. Piano is also a string instrument, where you make the strings sound by playing on the keys. The “strings” in our instrument are thin wooden sticks that a fastened between blocks, touching them makes them vibrate.
As it was again a hybrid online workshop then we created a small take-home packages for the participants to be picked up from Vivistop. Hereby it is appropriate to thank Lamuu for the ice-cream sticks and cups (later to be used for amplifying the sound).
Before putting all the pieces in place we talked a little about the science of sound, how can we create and why do we hear it. Sound is created by vibrations (vibrating strings in the case of a guitar) that is spread and carried through air. Sound does travel also in water, but not in a vacuum like space, where there is nothing that would carry the vibrations forward. Different strings with different frequencies create different sound. High frequencies are for high notes and low frequencies are for low notes. The frequency is dependent also on the material used for the string and how much tension is there. Here is an excellent video illustrating the vibrations (super slow motion to make it visible to eye):
In our case the determining factor is the length of the sticks and this is what we went to experiment with. First we fastened 6 ice-cream sticks to the wooden blocks. Although there are only 2 screws needed it turned out to be a bit of a challenges a the sticks wanted to escape and wiggle away from their new role. It turned out also that if you do not have the right Phillips head screwdriver you can still turn in the screws with a lot of patience and persistence.
The next step was tuning the instruments. A tuned instruments means every strings creates the right note on the right frequency and also all the strings are in the same frequency interval (octave). An out of tune instruments sound unpleasant to our ear. For tuning we fastened the screws so that we still can move the strings a little bit and and then used a phone app called Tuner T1 to verify the notes and frequencies. It was no easy task! Even if you could get one string to sound perfect the neighbours did not follow or could not repeatedly sound the same. We learned first had why the masters of musical instruments are very picky both on materials and technology and why metal for strings is preferred. The wooden sticks can be different both from the material, flexibility, they could have cracks and all that leads to a very challenging tuning process.
And finally we also experimented with amplifying the sound. For that we used the ice-cream cup and when placing the instrument on top if it the sound was indeed louder. This principle for a sound box is used in a lot of instruments to amplify the sound, what it does it multiplies the vibrations from the strings and more vibrations mean more stronger sound.
It is a really easy instrument to assemble and the materials are quite easy to be found— just don’t throw away the ice-cream sticks. But what it does is show a lot of aspects around sound and well sounding sound. Also, if making and tuning a multi-string instrument is a challenge, you can try most of it also with a ruler. Place it over the edge of the table, fire app the tuning app and observer how different length and vibrations create different notes.
Workshop and images: Timo Varblas
Text: Heikko Ellermaa