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add-ons:impedance-analyzer:diy-speaker [2021/06/22 17:54] – Arthur Brownadd-ons:impedance-analyzer:diy-speaker [2022/10/04 11:38] (current) – external edit 127.0.0.1
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   * breadboard   * breadboard
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-**Note:** //All the above components can be found in the [[https://store.digilentinc.com/analog-parts-kit-by-analog-devices-companion-parts-kit-for-the-analog-discovery/|Analog Parts Kit]].//+**Note:** //All the above components can be found in the [[https://digilent.com/shop/analog-parts-kit-by-analog-devices-companion-parts-kit-for-the-analog-discovery/|Analog Parts Kit]].//
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 ===== Using the Impedance Analyzer ===== ===== Using the Impedance Analyzer =====
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-The first step in building your own speaker is to analyze the most significant properties of an existing speaker. You can use the one found in the [[https://store.digilentinc.com/analog-parts-kit-by-analog-devices-companion-parts-kit-for-the-analog-discovery/|Analog Parts Kit]].+The first step in building your own speaker is to analyze the most significant properties of an existing speaker. You can use the one found in the [[https://digilent.com/shop/analog-parts-kit-by-analog-devices-companion-parts-kit-for-the-analog-discovery/|Analog Parts Kit]].
  
 Use the Impedance Analyzer to measure the magnitude of the impedance of the speaker between 20 Hz and 20 KHz, as these are the lower and the upper limits of human hearing. In this case, the magnitude of the impedance is almost constant, around 8 Ω, for a while, then starts to increase. Use the Impedance Analyzer to measure the magnitude of the impedance of the speaker between 20 Hz and 20 KHz, as these are the lower and the upper limits of human hearing. In this case, the magnitude of the impedance is almost constant, around 8 Ω, for a while, then starts to increase.
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 Now cut a piece of copper wire, around 1 m to 1.5 m, and wind it around the marker to make a coil. Use sandpaper to clean both ends of the wire. Now cut a piece of copper wire, around 1 m to 1.5 m, and wind it around the marker to make a coil. Use sandpaper to clean both ends of the wire.
  
-Measure the magnitude of the impedance of this small coil. In this case 1.5m of wire was used and the resulting magnitude is around 0.9 Ω. Use the following formula to calculate the length of the wire needed for the speaker: $l_{wire}=l_{small-wire}*\frac{|Z|_{speaker}}{|Z|_{small-wire}}=1.5m*\frac{8Ω}{0.9Ω}$.+Measure the magnitude of the impedance of this small coil. In this case, 1.5m of wire was used, and the resulting magnitude is around 0.9 Ω. Use the following formula to calculate the length of the wire needed for the speaker: $l_{wire}=l_{small-wire}*\frac{|Z|_{speaker}}{|Z|_{small-wire}}=1.5m*\frac{8Ω}{0.9Ω}$.
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-Calculate how much wire do you need, then use the tape measure and cut it. Wind the wire around the marker. Use the sandpaper to clean the ends, then measure the magnitude of its impedance. You should get a value close to the speaker's magnitude of impedance. In this case, the value starts a bit below 8 Ω and starts to increase earlier, but that increase will only affect high pitch sounds.+Calculate how much wire you need, then use the tape measure and cut it. Wind the wire around the marker. Use the sandpaper to clean the ends, then measure the magnitude of its impedance. You should get a value close to the speaker's magnitude of impedance. In this case, the value starts a bit below 8 Ω and starts to increase earlier, but that increase will only affect high pitch sounds.
  
 If you are satisfied with the results, solder two thicker wires to the ends of your coil. If you are satisfied with the results, solder two thicker wires to the ends of your coil.
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 ===== Testing ===== ===== Testing =====
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 Connect your PC or phone to the audio input and play some music. Use the potentiometer to turn up the volume. Apply "sound effects" by slightly moving the magnets towards one side of the coil. Connect your PC or phone to the audio input and play some music. Use the potentiometer to turn up the volume. Apply "sound effects" by slightly moving the magnets towards one side of the coil.
  
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 The coil of the speaker might get hot if too much current flows through it! The coil of the speaker might get hot if too much current flows through it!
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