Sounds Of Music C

wec01
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Re: Sounds Of Music C

Post by wec01 » February 27th, 2019, 4:37 pm

mjcox2000 wrote:A percussionist strikes a chime bar and measures some of its resonant frequencies:
Fundamental: 80 Hz
1st overtone: 220 Hz
2nd: 430 Hz
3rd: 715 Hz
4th: 1070 Hz
5th: 1500 Hz

What note would the ear most likely hear based on this series of overtones? What overtones contribute the most to the perception of this note?
I'm not sure about this, but I think the ear would hear 5 Hz largely because of the 715 Hz which is not a harmonic of anything in common with the other overtones besides 5 Hz. Similarly, 1070 Hz and 430 Hz are only both harmonics of 10 Hz (which isn't shared with 715 Hz), so that leaves 5 Hz.
2019 Division C Nationals Medals:
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5th place Sounds of Music
2nd place Thermodynamics

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Re: Sounds Of Music C

Post by mjcox2000 » February 27th, 2019, 4:50 pm

wec01 wrote:
mjcox2000 wrote:A percussionist strikes a chime bar and measures some of its resonant frequencies:
Fundamental: 80 Hz
1st overtone: 220 Hz
2nd: 430 Hz
3rd: 715 Hz
4th: 1070 Hz
5th: 1500 Hz

What note would the ear most likely hear based on this series of overtones? What overtones contribute the most to the perception of this note?
I'm not sure about this, but I think the ear would hear 5 Hz largely because of the 715 Hz which is not a harmonic of anything in common with the other overtones besides 5 Hz. Similarly, 1070 Hz and 430 Hz are only both harmonics of 10 Hz (which isn't shared with 715 Hz), so that leaves 5 Hz.
If that were true, no tone composed of multiple frequencies that are even slightly off harmonic would ever be perceived as anything but an extremely low frequency, yet we still hear these tones as a reasonable frequency. Try again.
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Re: Sounds Of Music C

Post by Birdmusic » March 1st, 2019, 4:47 pm

mjcox2000 wrote:A percussionist strikes a chime bar and measures some of its resonant frequencies:
Fundamental: 80 Hz
1st overtone: 220 Hz
2nd: 430 Hz
3rd: 715 Hz
4th: 1070 Hz
5th: 1500 Hz

What note would the ear most likely hear based on this series of overtones? What overtones contribute the most to the perception of this note?
Wouldn't we need the spectrogram to do this? Or are we assuming all frequencies are at the same volume?

Most instruments are loudest at their fundamental, or 80 Hz (slightly flat E2). I'm not sure about the second one.
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Re: Sounds Of Music C

Post by mjcox2000 » March 2nd, 2019, 6:16 am

Birdmusic wrote:
mjcox2000 wrote:A percussionist strikes a chime bar and measures some of its resonant frequencies:
Fundamental: 80 Hz
1st overtone: 220 Hz
2nd: 430 Hz
3rd: 715 Hz
4th: 1070 Hz
5th: 1500 Hz

What note would the ear most likely hear based on this series of overtones? What overtones contribute the most to the perception of this note?
Wouldn't we need the spectrogram to do this? Or are we assuming all frequencies are at the same volume?

Most instruments are loudest at their fundamental, or 80 Hz (slightly flat E2). I'm not sure about the second one.
It’s relevant that these are chimes. Chimes’ perceived notes are determined in a specific way based on their various resonant frequencies. You shouldn’t need a spectrogram, but if you want, you can look up a generic chime spectrogram.
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Re: Sounds Of Music C

Post by wec01 » March 2nd, 2019, 6:52 am

mjcox2000 wrote:
Birdmusic wrote:
mjcox2000 wrote:A percussionist strikes a chime bar and measures some of its resonant frequencies:
Fundamental: 80 Hz
1st overtone: 220 Hz
2nd: 430 Hz
3rd: 715 Hz
4th: 1070 Hz
5th: 1500 Hz

What note would the ear most likely hear based on this series of overtones? What overtones contribute the most to the perception of this note?
Wouldn't we need the spectrogram to do this? Or are we assuming all frequencies are at the same volume?

Most instruments are loudest at their fundamental, or 80 Hz (slightly flat E2). I'm not sure about the second one.
It’s relevant that these are chimes. Chimes’ perceived notes are determined in a specific way based on their various resonant frequencies. You shouldn’t need a spectrogram, but if you want, you can look up a generic chime spectrogram.
Since it's a chime, the fourth fifth and sixth overtones should have frequencies at a ratio of about 81:121:169, which is consistent here. This is close to a ratio of 2:3:4 which makes the perceived pitch about half the frequency of the fourth overtone, or 357.5 Hz.
2019 Division C Nationals Medals:
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5th place Sounds of Music
2nd place Thermodynamics

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Re: Sounds Of Music C

Post by mjcox2000 » March 2nd, 2019, 8:31 am

wec01 wrote:
mjcox2000 wrote:
Birdmusic wrote:
Wouldn't we need the spectrogram to do this? Or are we assuming all frequencies are at the same volume?

Most instruments are loudest at their fundamental, or 80 Hz (slightly flat E2). I'm not sure about the second one.
It’s relevant that these are chimes. Chimes’ perceived notes are determined in a specific way based on their various resonant frequencies. You shouldn’t need a spectrogram, but if you want, you can look up a generic chime spectrogram.
Since it's a chime, the fourth fifth and sixth overtones should have frequencies at a ratio of about 81:121:169, which is consistent here. This is close to a ratio of 2:3:4 which makes the perceived pitch about half the frequency of the fourth overtone, or 357.5 Hz.
That looks right! One thing — it seems like you kept saying “overtone” when you meant “mode”. Your turn!
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Re: Sounds Of Music C

Post by wec01 » March 2nd, 2019, 2:44 pm

Yeah, I accidentally mixed the two words up

Here are some general violin questions:
1) What is the interval between adjacent strings of the violin?
2) What is the technique of plucking a violin (or other stringed instruments in general) called?
3) How does a bowed instrument produce noise and how does rosin help with this?
2019 Division C Nationals Medals:
4th place Fossils
5th place Sounds of Music
2nd place Thermodynamics

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Re: Sounds Of Music C

Post by mjcox2000 » March 2nd, 2019, 8:39 pm

wec01 wrote:Yeah, I accidentally mixed the two words up

Here are some general violin questions:
1) What is the interval between adjacent strings of the violin?
2) What is the technique of plucking a violin (or other stringed instruments in general) called?
3) How does a bowed instrument produce noise and how does rosin help with this?
1. Perfect fifth
2. Pizzicato
3. The bow continually excites the string for a sustained sound; rosin increases friction to privide for better stick-slip motion.
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wec01
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Re: Sounds Of Music C

Post by wec01 » March 3rd, 2019, 6:15 pm

mjcox2000 wrote:
wec01 wrote:Yeah, I accidentally mixed the two words up

Here are some general violin questions:
1) What is the interval between adjacent strings of the violin?
2) What is the technique of plucking a violin (or other stringed instruments in general) called?
3) How does a bowed instrument produce noise and how does rosin help with this?
1. Perfect fifth
2. Pizzicato
3. The bow continually excites the string for a sustained sound; rosin increases friction to privide for better stick-slip motion.
Yep, your turn!
2019 Division C Nationals Medals:
4th place Fossils
5th place Sounds of Music
2nd place Thermodynamics

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Re: Sounds Of Music C

Post by mjcox2000 » March 3rd, 2019, 8:35 pm

1. What is a pedal tone?
2. On which instruments can a pedal tone be played?
3. Is a pedal tone in the instrument’s harmonic series? Is it a resonant frequency for the instrument? What tradeoffs do instrument designers make relating to pedal tones?
4. Would a player be more likely to play pedals when warming up or warming down? Why?
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