Introduction: (Initial Observation)
Music and noise are similar in many ways, but also different in some important ways. While noise is disturbing and often nuisance, music is relaxing, exciting, and has positive affects on human emotion. Human feelings toward music or noise can be an unconscious state of the mind or it may be a learned reaction and perception. For example if we play a music for a person who has never heard a music in his life, he may or may not show any reaction to that music. Also we don’t know what is the reaction of animals, specially monkeys and other primates to music.
Knowing these will help us to better focus our research and know if we should be searching the physics and mechanics of music or we should be searching human brain and nervous system for it’s specific reaction toward music and noise. In this project we will attempt to understand and describe the differences between Music and Noise.
Information Gathering:
In order to find out the differences between music and noise, we start investigating the known properties or characteristics of music and sound. We will try to see what characteristics are shared between these two and what are the differences. We will also consider possible effects of external factors such as human brain and the way that it processes each sound element.
In other words we want to find out what factors affect our mind to decide that a specific sound is a music or a noise?
After we identify these possible factors, we need to design an experiment or a series of experiments to test the effect of each factor.
Factors that may affect a sound to be recognized as noise or music are:
- Pitch: Refers to the highness or lowness of a sound. A synonym for pitch is note. Strictly speaking, pitch is a function of frequency
- Loudness: A note with a large amplitude is loud, one with a small amplitude is soft. Loudness is usually measured on the deciBell scale, which is determined by the maximum pressure change that the note (or other noise) produced
- Rhythm: The subdivision of a span of time into perceptible sections; the grouping of musical sounds, principally by means of duration and stress.
- Melody: A series of musical notes arranged in succession, in a particular rhythmic pattern, to form a recognizable unit.
- harmony: Harmony is the relation of notes to notes and chords to chords as they are played simultaneously. Harmonic “patterns” are established from notes and chords in successive order.
- Cognition: Costumes, culture and memories that affect our perception from a sensory stimuli such as sound.
Before you go to the experiment section, please visit and review these links.
http://www.omnidisc.com/MUSIC/Lecture1.html
http://w3.rz-berlin.mpg.de/cmp/g_rhythm.html
In order to find out if animals have any feelings toward music we search the Internet with keywords “Animal Music Reaction”. Following are some results:
http://www.music-cog.ohio-state.edu/Music829D/Notes/LeDoux.html
Question/ Purpose:
What do you want to find out? Write a statement that describes what you want to do. Use your observations and questions to write the statement.
The purpose of this project is to compare music versus noise and discover the factors that affect human perception from sounds.
Identify Variables:
When you think you know what variables may be involved, think about ways to change one at a time. If you change more than one at a time, you will not know what variable is causing your observation. Sometimes variables are linked and work together to cause something. At first, try to choose variables that you think act independently of each other.
Independent (manipulated) variables that may affect a sound to be recognized as noise or music are:
- Pitch: Refers to the highness or lowness of a sound. A synonym for pitch is note. Strictly speaking, pitch is a function of frequency
- Loudness: A note with a large amplitude is loud, one with a small amplitude is soft. Loudness is usually measured on the decibel scale, which is determined by the maximum pressure change that the note (or other noise) produced
- Rhythm: The subdivision of a span of time into perceptible sections; the grouping of musical sounds, principally by means of duration and stress.
- Melody: A series of musical notes arranged in succession, in a particular rhythmic pattern, to form a recognizable unit.
- Harmony: Harmony is the relation of notes to notes and chords to chords as they are played simultaneously. Harmonic “patterns” are established from notes and chords in successive order.
- Cognition: Costumes, culture and memories that affect our perception from a sensory stimuli such as sound.
The above independent variables may be studied one at a time in separate experiments. (So for each experiment you only study one of the above variables).
Dependent variable (also known as responding variable) is our perception of the sound (Noise or Music).
Constants are all other variables. For example in experiment number 1 that you study the effect of sound pitch, constants are: loudness, rhythm, melody, harmony and cognition.
Controlled variable is the environment sound.
Hypothesis:
Based on your gathered information, make an educated guess about what types of things affect the system you are working with. Identifying variables is necessary before you can make a hypothesis.
My hypothesis is that rhythm is an important factor in recognizing a sound as a music. Rhythm makes every piece of sound to be expected, not a surprise. Rhythm allows us to align our thoughts and our motions in a harmony and dance.
Melody is another important factor. certain notes in a special order are pleasant to our ears. Changing the notes or changing their order can easily transform a music to a noise. A group of notes that can make a melody are also known as tune.
Cognition is another important factor because we do not usually enjoy the music of other countries and cultures.
Finally I think that pitch, loudness and harmony are also components of noise and normally have little or no effect in our perception of sound as noise or music.
Experiment Design:
Design an experiment to test each hypothesis. Make a step-by-step list of what you will do to answer each question. This list is called an experimental procedure. For an experiment to give answers you can trust, it must have a “control.” A control is an additional experimental trial or run. It is a separate experiment, done exactly like the others. The only difference is that no experimental variables are changed. A control is a neutral “reference point” for comparison that allows you to see what changing a variable does by comparing it to not changing anything. Dependable controls are sometimes very hard to develop. They can be the hardest part of a project. Without a control you cannot be sure that changing the variable causes your observations. A series of experiments that includes a control is called a “controlled experiment.”
For these experiments you will create different sounds and ask a listener to classify the sound as a noise, pleasant sound or music.
Experiment 1:
Pleasant sound is one of the important elements of music. In this experiment we will study the effect of pitch, frequency or note on making a pleasant sound. You can be the listener for your own experiments if you have nobody else to listen. In this experiment you will use a synthesizer.
Procedure:
- Use a synthesizer to play some single notes, each for about 3 seconds and see which notes are more pleasant? (High notes or Low notes).
- Mix 2, 3 or more notes and play them together? See the effect of this mix on making the sound more or less pleasant.
- Place some metal, wood and plastic pieces in a metal can or box and shake it for 3 seconds. How pleasant is the sound?
- Repeat the previous experiment with only metal, only plastic or only wood pieces. How pleasant is the sound?
You can record 3 or 5 second of each sound in a tape with about 10 seconds silent intervals. Then use your tape and ask others to listen and rate each section with a number from 0 for noise up to 100 for a pleasant note.
Some sounds are pleasant and some are a noise.
Compare the two waves on the right.
A pleasant sound has a regular wave pattern. The pattern is repeated over and over. But the waves of noise are irregular. They do not have a repeated pattern.
By completing the above experiment, you should be able to decide:
- Which notes or frequencies are pleasant and which are not.
- What type of changes in a sound, makes it an unpleasant noise?
Experiment 2:
Introduction: Every audio device is equipped with a volume control knob that allows us to adjust the loudness of sound produced by that device. In this experiment we will try to see if loudness has any affect on our perception of a sound. Can we perceive a music as a noise just by reducing or increasing the loudness?
Procedure:
- Place a music tape or CD (that you have never listened to) in a player and bring the volume all the way down.
- Start to play and then increase the volume gradually.
- When the volume is very low and you can not clearly hear all the sounds ask yourself or a listener how pleasant it is? is it noise or music? Does loudness affect our perception of sound? Record the number of people with positive answers in your results table.
- Increase the volume for one degree* and ask the questions again.
- Repeat increasing the volume and asking question at least 5 more times and record your results.
Warning: I do not suggest you to do the same test with very loud music because listening to very loud sound can cause permanent damage to your ears and hearing system.
This is a sample of a results table:
Perception of music when played at a very low volume
| Volume level | People reported pleasant | People perceived music |
| 1 | ||
| 2 | ||
| 3 | ||
| 4 | ||
| 5 |
* What is the volume level?
Depending on your audio device you may need to increase the volume by pushing a button or turning a knob. Count each quick touch of the button as one degree volume. If you have a knob, then rotate it about 1 degree for each volume level. Use a protractor if you are not sure how much is one degree.
Make a graph
You may make a graph to visually present your results. Make a bar graph with one vertical bar for each level of volume you test. Label the bars with the same numbers as volume levels. The height of each bar is the number of people perceived the sound as music. For example you may make one of the bars 3 inches to represent 3 people.
Experiment 3:
Rhythm is a main component of every music and sometimes the only component of martial music. Playing drum for example in some cases is just producing the rhythm. In this experiment we will take the rhythm out of a well known music and evaluate the result.
Procedure:
- Think about a music that you can play. Use a synthesizer to play it with a rhythm and record it.
- Play the same music again but without rhythm, instead of rhythm use a random pulse generated by yourself, someone else or a natural phenomena such as rain drops on a metal can. Record this too.
- Play both products for others and ask them to rate it between 0 for noise and 100 for music.
Experiment 4:
Certain notes in a specific order will sound pleasant. Such an order is called melody. A music will lose its melody if you replace one or two of the notes with another note. It will also lose its melody if you change the order of playing the notes. In this experiment we will test both possibilities and compare the results.
Procedure:
- Use a synthesizer to play a music and record it.
- Replace one or two notes in your music with any other note that you choose and play again and record it.
- Play the same music backward (changing the order of notes)
- Play all 3 recordings for some listeners and ask them to rate each play with numbers from 0 for noise and 100 for music.
Experiment 5:
In a large orchestra, harmony is the main element that creates a pleasant echo, volume and excitement. When all players play in harmony, they follow the same rhythm and matching notes. In this experiment we will test the effect of harmony in our perception of sound. For this part of experiment you need a helper that can play the same or another similar device with you.
Procedure:
- Select a music that both of you can play. You can use identical instruments or different instruments. Start to play together with a rhythm and record it.
- Each of you play the same music separately and record it in two different tapes.
- Play the last two tapes together and record the combination in another tape that we call it combination tape.
- Now play your first tape and combination tape for some listeners and ask them to rate each tape with numbers from 0 for noise to 100 for music.
In your first tape and combination tape, you are using the same notes and the same music. The only difference is that in combination tape, each player is following a different timing (rhythm). You can do a similar harmony experiment by using the same rhythm, but playing two different music. Then you can compare playing same music with playing two different music.
Experiment 6:
Maybe we have learned to associate music with our happy moments and noise with our sad or trouble moments. Maybe noise and music are just two different sounds and our perception is just based on our past memories. Maybe if we were slaves and we would listen to music only while being tortured and we would listen to noise while resting or having food, we would think differently about noise and music.
In this experiment we will try to see how much our previous memories affect our perception of sounds and the way that we rate them as music or noise.
To do this experiment right, we needs to travel to different countries and repeat the experiment with subjects who have different cultures, different backgrounds and different memories. Specially the test needs to be performed on members of communities that have no radio or television yet. So what we do here is just a simplified version of this experiment.
Procedure:
- Collect samples (15 seconds each) of music from different cultures. Every piece that you select must be known to you. At least you will need to know the name of country, language and music style of that piece.
- Play this music samples for individuals with different cultures and backgrounds and ask them to rate each piece with numbers from 0 for unpleasant noise up to 100 for a pleasant music.
Write a list of your music samples in a table like this and make multiple copies of that to be used for rating by different listeners.:
Listener: (Country: ———-, Language: ———-, Age: ———-)
| Music Name | Country of Origin | Music Style | Music Language even if it has no Lyrics | Rate (0 to 100) |
Materials and Equipment:
List of material can be extracted from the experiment section.
Results of Experiment (Observation):
Experiments are often done in series. A series of experiments can be done by changing one variable a different amount each time. A series of experiments is made up of separate experimental “runs.” During each run you make a measurement of how much the variable affected the system under study. For each run, a different amount of change in the variable is used. This produces a different amount of response in the system. You measure this response, or record data, in a table for this purpose. This is considered “raw data” since it has not been processed or interpreted yet. When raw data gets processed mathematically, for example, it becomes results.
Calculations:
Description
Summary of Results:
Summarize what happened. This can be in the form of a table of processed numerical data, or graphs. It could also be a written statement of what occurred during experiments.
It is from calculations using recorded data that tables and graphs are made. Studying tables and graphs, we can see trends that tell us how different variables cause our observations. Based on these trends, we can draw conclusions about the system under study. These conclusions help us confirm or deny our original hypothesis. Often, mathematical equations can be made from graphs. These equations allow us to predict how a change will affect the system without the need to do additional experiments. Advanced levels of experimental science rely heavily on graphical and mathematical analysis of data. At this level, science becomes even more interesting and powerful.
Conclusion:
Using the trends in your experimental data and your experimental observations, try to answer your original questions. Is your hypothesis correct? Now is the time to pull together what happened, and assess the experiments you did.
Related Questions & Answers:
What you have learned may allow you to answer other questions. Many questions are related. Several new questions may have occurred to you while doing experiments. You may now be able to understand or verify things that you discovered when gathering information for the project. Questions lead to more questions, which lead to additional hypothesis that need to be tested.
Possible Errors:
If you did not observe anything different than what happened with your control, the variable you changed may not affect the system you are investigating. If you did not observe a consistent, reproducible trend in your series of experimental runs there may be experimental errors affecting your results. The first thing to check is how you are making your measurements. Is the measurement method questionable or unreliable? Maybe you are reading a scale incorrectly, or maybe the measuring instrument is working erratically.
If you determine that experimental errors are influencing your results, carefully rethink the design of your experiments. Review each step of the procedure to find sources of potential errors. If possible, have a scientist review the procedure with you. Sometimes the designer of an experiment can miss the obvious.
References:
Visit your local library and find books related to music. List such books as your references in addition to the Internet references including this website.
Following are some additional Internet literature for your review:
