I need to know how to make a glockenspiel for this HUUUGE science competition we're having. I have to make the keys of my glockenspiel F4-F5. I found a website, but I have a lot of trouble understanding how long to cut the pipes for the right frequency. Well, I need to know how to find "A". Here's an excerpt:
Once you buy your pipe, the only thing you can really control is the length of the pipes. The longer the pipe, the lower the main frequency. The formula is:
f=A/L2 (L2 means L squared)
Where f is the frequency, L is the length and A is a number that could in principle be calculated from the thickness of the pipe walls, the diameter of the pipes and the speed of sound in the material. In theory, you could measure the diameter of the pipes and the thickness of the pipe walls, and then precisely calculate A and figure out how long your pipes should be for the desired frequencies. The problem with that is that it is very hard to measure the thickness of the pipe walls and diameter of the pipes with sufficient precision. And you can't just use my data, because every pipe will be a bit different. Instead, we will cut a test pipe section, measure its length, use a mobile phone app to measure the frequency, and then use that to calculate A.
See what I mean? I don't even get what she means to find A! She never said multiply this or divide or add this at all! This is a really big deal for me, and the length of the pipes depends on the frequency EXACTLY. What does she mean?! Here's the link http://www.instructables.com/id/Copper-p...
PLEEEASE help! What is A?!?! HOW do you find A?!?
Once you buy your pipe, the only thing you can really control is the length of the pipes. The longer the pipe, the lower the main frequency. The formula is:
f=A/L2 (L2 means L squared)
Where f is the frequency, L is the length and A is a number that could in principle be calculated from the thickness of the pipe walls, the diameter of the pipes and the speed of sound in the material. In theory, you could measure the diameter of the pipes and the thickness of the pipe walls, and then precisely calculate A and figure out how long your pipes should be for the desired frequencies. The problem with that is that it is very hard to measure the thickness of the pipe walls and diameter of the pipes with sufficient precision. And you can't just use my data, because every pipe will be a bit different. Instead, we will cut a test pipe section, measure its length, use a mobile phone app to measure the frequency, and then use that to calculate A.
See what I mean? I don't even get what she means to find A! She never said multiply this or divide or add this at all! This is a really big deal for me, and the length of the pipes depends on the frequency EXACTLY. What does she mean?! Here's the link http://www.instructables.com/id/Copper-p...
PLEEEASE help! What is A?!?! HOW do you find A?!?
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A usual glockenspiel has neither pipes nor a musical keyboard; see:
"Google image for glockenspiel":
http://www.google.com/search?q=glockensp...
"Google image for musical keyboard":
http://www.google.com/search?q=musical+k...
"Copper pipe glockenspiel":
http://www.instructables.com/id/Copper-p...
Citation: "You now have is your frequency f and your length L. Since f = A / L², you (or your student(s) if old enough) can solve for A and find A = f L². Just make sure to use the same units of length throughout the project. I recommend millimeters. For instance, if your length were 223 mm, and you measured a frequency of 1359 Hz, you would have A = (1359) (2232) = 67,581,711. The student(s) can figure out the units if old enough. A Hertz is in units of 1/s, so if your lengths are in millimeters, A will be in mm²/s."
Help: "Easy DIY Design and Build - Tubular-Bell - Tubes, Pipes or Rods":
http://home.fuse.net/engineering/Chimes....
Cheers ebs
"Google image for glockenspiel":
http://www.google.com/search?q=glockensp...
"Google image for musical keyboard":
http://www.google.com/search?q=musical+k...
"Copper pipe glockenspiel":
http://www.instructables.com/id/Copper-p...
Citation: "You now have is your frequency f and your length L. Since f = A / L², you (or your student(s) if old enough) can solve for A and find A = f L². Just make sure to use the same units of length throughout the project. I recommend millimeters. For instance, if your length were 223 mm, and you measured a frequency of 1359 Hz, you would have A = (1359) (2232) = 67,581,711. The student(s) can figure out the units if old enough. A Hertz is in units of 1/s, so if your lengths are in millimeters, A will be in mm²/s."
Help: "Easy DIY Design and Build - Tubular-Bell - Tubes, Pipes or Rods":
http://home.fuse.net/engineering/Chimes....
Cheers ebs