Sounds of Music C

[095067]

Do you guys have any recommendations on where to find information of how to do the math equations on the written portion? Thanks!

[glin1011]

The Sounds of Music tests usually involve different physics equations and it can be a variety of equations, however the site such as the PhysicsClassroom has been proven helpful for me when it comes to practicing equations.

My binder currently has a variety of notes from my former Physics class last year that relates to the physics of sound - but the PhysicsClassroom not only has majority of the equations, but it also has practice equations that you can work on.

It’s a really good source, especially a good foundation to start off with when it comes to your binder.

There’s other sources out there as well - but this is a popular source as long as you read through it wisely.

[CalColin]

Hey folks, I was the ES for GGSO (although I did not write the test). With a sample size of n=49, I think it may benefit some competitors for me to share some lessons learned from the tournament.

(1) Beware the octave jump! Many teams missed this. By the letter of the law, I have to assume that each note in the scale is played as intended unless otherwise stated. Consider marking in color the notes to be played for the scale and for Twinkle Twinkle.

(2) Make sure your fundamental sounds clear. I noticed that plucked string instruments and string instruments without a quality resonator suffered on clarity. Be mindful of percussive effects from strumming, strings rattling, and so on - this can obfuscate my readings and negatively impact your score.

(3) Likewise, if your instrument has a short decay time or produces weird overtones during decay, absolutely strike multiple times! This is the only way to guarantee your fundamental comes through clearly. Conversely, if your instrument has a long decay time, consider dampening the pitch you just played before proceeding to the next one.

(4) On logs: Many teams included either incorrect information or extraneous information. Be sure to relate a design element to the tuning of ONLY ONE pitch. The clearest way to do that is to set up a short data table. Generally, I think many teams are inclined to include too much information in their logs - the more succinct your logs are, the easier they are to grade! Also, be sure your pitch readings are experimental values, not theoretical. Last, make sure your labeled picture is clear enough for an event judge to easily read and interpret. An easy way to make sure your diagram is sufficiently clear is to ask a teammate (not your event partner) whether they can interpret it.

(5) No need to rush through Twinkle Twinkle. 4 bars at 4/4 time within 15 seconds implies a minimum tempo of 64 bpm - quite slow! A couple teams unfortunately went too fast and either hit a wrong note or lost their sense of rhythm. Target the tempo to your instrument's design.

GGSO competitors - I had a great time hearing your instruments this weekend. Good luck with the rest of the season, everyone!

[Galahad]

A string under tension is found to produce a frequency of 200 Hz when plucked. If the
tension applied to the string is doubled, what frequency will it now produce?

I need help with this question

[Nydauron]

A string under tension is found to produce a frequency of 200 Hz when plucked. If the
tension applied to the string is doubled, what frequency will it now produce?

I need help with this question

Just as a heads up, this would have probably best if you asked on the question marathon. But I digress... Here is the answer:

Click to Show Answer

Using the equations  and , we can substitute  in the second equation.


 Simplified for sanity's sake... 

Looking at this new equation, if we double tension  and keep everything else constant,  must increase by a factor of .

Therefore, the answer is  or .

[Galahad]

A string under tension is found to produce a frequency of 200 Hz when plucked. If the
tension applied to the string is doubled, what frequency will it now produce?

I need help with this question

Just as a heads up, this would have probably best if you asked on the question marathon. But I digress... Here is the answer:

Click to Show Answer

Using the equations  and , we can substitute  in the second equation.


 Simplified for sanity's sake... 

Looking at this new equation, if we double tension  and keep everything else constant,  must increase by a factor of .

Therefore, the answer is  or .

dang algebra. thanks! ill put my questions in the marathon next time. wasnt sure if i should since i wouldnt be able to explain the answer

[glin1011]

Just a random question, wondering if it helps anyone:

Is it worth it to listen to a few classical music compositions for the competition? I know one test was an auditory one and I was wondering if it was appropriate to listen a few, especially when it comes to reading the music sheets.

[builderguy135]

Just a random question, wondering if it helps anyone:

Is it worth it to listen to a few classical music compositions for the competition? I know one test was an auditory one and I was wondering if it was appropriate to listen a few, especially when it comes to reading the music sheets.

The aural section of the MIT test was done very similarly to the AP Music Theory test.

[terence.tan]

since my season has come to an end due to the cancellation of the NY State competition, I will be willing to share pictures of my build and tips. PM me if your interested
( i got a perfect score on my build at LISO and regionals. At SOUP i got 4 cents for 2 of my pitches and under 3 for the rest)

[gz839918]

At the two invitationals where I supervised, I used the pascioly.org applet whenever it could register the note, and I used Audacity as a backup. Audacity offered several advantages for use as a backup:

• It records anything. The pascioly.org web app did not read notes that were too silent, and without Audacity, some teams would have had to receive a skipped note even if I could hear a clear distinct pitch.
• I have control over analyzing pitch. pascioly.org is a black box with nuts and bolts I can't see. if pascioly.org suddenly jumps to a cents-off reading before returning to no note detected, I can't always tell whether the web app suddenly started working again, or whether its invisible internal machinery set off a false alarm by giving me an incorrect reading (for example, because of a spike in background noise).

Disadvantages of Audacity include...

• Audacity rounds fundamental and overtone frequencies to the nearest integer, which is not super great since several notes may be spaced within only a few hertz, and so this may increase the cent difference. Case in point, E₃ and F₃ are only 10 Hz away, and if Audacity rounds up by 1 Hz to the nearest integer, that could increase a team's cents error by around 10 cents for that note.
• Audacity can't discern when the frequency is not equal to the pitch, such as when partials move but spectral envelope (overall shape of the spectrogram) is unchanged. This problem is very rare for strings and pipes however, and I think I saw it only once.
• In some idiophones, there's no clear apparent pattern amongst partials. So what the heck do I measure? (I usually chose whatever peak frequency was closest to the target note, but due to the bullet point above, I know this wasn't a great idea because it resulted in huge cent differences from the target note. My reasoning was that it was better than giving teams zero points when pascioly.org stopped working.)

I prefer the pascioly.org web app over Audacity whenever I have a professional microphone, but since I can always see the raw waveform in Audacity, it helps if pascioly.org isn't working. I would discourage Audacity to event supervisors except as a backup. Another possible backup method which I haven't tried out is to use cell phone microphones with a tuning app. These days, even cell phone microphones are legit actually quite good.

Not specific to Audacity though, many compelling reasons exist for why pitch shouldn't be measured as the fundamental frequency. These issues could occur with the pascioly.org web app too; some supervisors simply choose to ignore the measured values and wait until pascioly.org displays the pitch they want it to display.

Update to this: if you're an event supervisor and you're using a Neewer microphone (the microphone recommended by SO Inc.), then Audacity will not work. Even if the microphone is working for literally everything else, including pascioly.org and Praat, it won't work with Audacity. On my Windows 10 Dell Inspiron laptop, I tested pascioly.org and Praat and Audacity one by one, and only Audacity would default to the built-in microphone on the computer while the others would pick up from the Neewer. I don't actually have an answer for why so enjoy the smiling shrug person instead ¯\_(ツ)_/¯

In short, avoid Audacity if you're using the Neewer microphone