alexpea
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I attend a music technology school, and I need to deliver in some papers tomorrow, answering several questions. I have problems understanding this one, however, and was hoping for some opinions:
"We usually describe sound in 3 dimensions. Time (s), Level (dB) and Frequency (Hz). How many milliseconds does it take to start the vibrations in a pianostring, in a trumpet-tone and in an organ-tone?"
1. I don't really understand the question here, cuz I don't know if the startpoint of the calculation should be upon the impact of the piano-key, or when the piano-hammer hits the string within the piano. The question doesn't state that the result should be audible, so it's just a matter of vibration within the string. And one vibration equals one periodic swing, which is different from each pianostring - due to different frequencies being generated.
2. The trumpet starts (I believe) when the first breath of air comes into the chamber. Then it's a matter of finding the frequency-response of a trumpet, and calculating the speed of sound together with the periodic swing, and the length of the chamber. However, I don't know the amount of reflections within the chamber before the sound reaches the end, so it seems impossible. Because a trumpet functions in a way of multiple reflections back and forth with resistors breaking up the waves to alter the timbre and pitch. I'd have to be a engineer/mathmatician/genius to calculate the time from initial breath to actual tone at the end.
3. The organ-tone is also very absurd to me, as it's produced by electric signals. So I have to calculate the time from the triggering of the electricity, until the actual reproduction of sound from the internal speakers. That again will vary from organ to organ, depending on impedance, wire-lengt, speaker-size and speaker-material.
Hmmm...though one, this. I have no idea how to approuch it what so ever. Help
"We usually describe sound in 3 dimensions. Time (s), Level (dB) and Frequency (Hz). How many milliseconds does it take to start the vibrations in a pianostring, in a trumpet-tone and in an organ-tone?"
1. I don't really understand the question here, cuz I don't know if the startpoint of the calculation should be upon the impact of the piano-key, or when the piano-hammer hits the string within the piano. The question doesn't state that the result should be audible, so it's just a matter of vibration within the string. And one vibration equals one periodic swing, which is different from each pianostring - due to different frequencies being generated.
2. The trumpet starts (I believe) when the first breath of air comes into the chamber. Then it's a matter of finding the frequency-response of a trumpet, and calculating the speed of sound together with the periodic swing, and the length of the chamber. However, I don't know the amount of reflections within the chamber before the sound reaches the end, so it seems impossible. Because a trumpet functions in a way of multiple reflections back and forth with resistors breaking up the waves to alter the timbre and pitch. I'd have to be a engineer/mathmatician/genius to calculate the time from initial breath to actual tone at the end.
3. The organ-tone is also very absurd to me, as it's produced by electric signals. So I have to calculate the time from the triggering of the electricity, until the actual reproduction of sound from the internal speakers. That again will vary from organ to organ, depending on impedance, wire-lengt, speaker-size and speaker-material.
Hmmm...though one, this. I have no idea how to approuch it what so ever. Help