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You can extract order waveforms to isolate specific orders from a sound or vibration signal. An order waveform provides detailed information about the specific orders you extracted from the input signal. You then can perform further analysis, such as sound playback and sound synthesis, on these significant orders.

Use the Order Waveform Express VI to extract order waveforms. As you observed with the Colormap, Order power spectrum, and Magnitude plots, the seventh order is one of the strongest orders in the computer fan run-up data. You can use the Order Waveform Express VI to extract and display the order waveform of the seventh order.

Complete the following steps to extract and display the order waveform of the seventh order from the computer fan run-up data.

1. Place the Order Waveform Express VI on the block diagram of the Getting Started Exercise VI. A configuration dialog box appears.
   
    
   
   
2. Click the OK button to save the current configuration and close the configuration dialog box. In this application, you can use the default configuration settings when you run the Order Waveform Express VI for the first time.
3. Wire the waveform signal output of the oax_Load Data (Analog Tacho, single channel) VI to the input signal input of the Order Waveform Express VI.
4. Wire the speed profile output of the Analog Tacho Processing Express VI to the speed profile input of the Order Waveform Express VI.
5. Wire the order list output of the Order Waveform Express VI to the Order list indicator.
6. Wire the order waveform output of the Order Waveform Express VI to the Order waveform indicator.
   
   The block diagram should appear similar to the following block diagram.

7. Run the Getting Started Exercise VI.
8. Double-click the Order Waveform Express VI to display the configuration dialog box. You can see the colormap of the computer fan run-up data in the Colormap plot.
9. On the Order Selection page, set Order to preview to 7.
10. Click the Extract button to extract the order waveform of the seventh order and to add the seventh order to the Output list.
11. Click the OK button to save the current configuration and close the configuration dialog box.
12. Run the Getting Started Exercise VI again to extract and display the waveform of the seventh order of the computer fan run-up data.
13. Save this VI.

On the front panel, click the Order Waveform tab to display the Order waveform plot of the seventh order, as shown in the following figure.

You also can use the Order Waveform Express VI to extract order waveform of combined orders of a signal that generate the greatest amplitude, or produce the strongest noise. As you observed with the Colormap, Order power spectrum, and Magnitude plots, the fourth, seventh, and eighth orders have relatively strong amplitudes in the computer fan run-up data.

Complete the following steps to extract and display the waveforms of the combination of the fourth, seventh, and eighth orders.

1. Press the <Ctrl-E> keys to switch to the block diagram of the Getting Started Exercise VI.
2. Double-click the Order Waveform Express VI to display the configuration dialog box.
3. On the Order Selection page, remove the checkmark from the Auto export checkbox.
4. Set Order to preview to 4.
5. Click the Extract button to extract the order waveform of the fourth order.
6. Set Order to preview to 8.
7. Click the Extract button to extract the order waveform of the eighth order.
8. In the Extracted orders list, press the <Ctrl> or <Shift> key to select the fourth, seventh, and eighth orders simultaneously.
9. Click the Export button to export the combined order waveform of the fourth, seventh, and eighth orders to the block diagram. Clicking the Export button also adds the combination of the fourth, seventh, and eighth orders to the Output list.
10. Click the OK button to save the current configuration and close the dialog box.
11. Run the Getting Started Exercise VI.
12. Save this VI.

On the front panel, the Order waveform plot now displays both the waveform of the seventh order and the waveform of the combination of the fourth, seventh, and eighth orders, as shown in the following figure.

You can add different order waveforms together in different combinations. You then can play back the resulting waveforms as sounds and determine which combination is the most pleasing to the ear. By playing the sounds and testing by ear, you can determine how to reduce the harshness of the signal and how to remove undesirable sounds and vibrations.

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