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Use this method if you use a calibrator or if you are able to measure the vibration of your vibrational transducer. For example a shaker with know vibration (displacement, velocity or acceleration).
If you don’t have access to such equipment, but if the sensitivity of your transducer is known you can still do the calibration. To do this, go to the next section and skip the rest of this section.
To do the combined
calibration, select the 
settings shown in the figure below.
In step 3 shown in the
figure above, click the 
button to open the dialog box shown below. If you have an
external device to generate the vibration for the calibration, select 
in step 1. Then the dialog box
will be displayed as shown below.
In step 2 select the
frequency of the device you are using for the calibration. The device must
generate a vibration at a single frequency. In the list box you can type in any
frequency, in the example above it is set to 
.
In step 3a connect your transducer to the vibration generator. For example, if your transducer is an accelerometer and your vibration generator is a shaker, then connect the accelerometer to the shaker.
In step 3b click the
button, after doing this a
dialog box will be displayed showing the calibration input level. It should be
adjusted so it is in the range -30 to 0 dBFS.
In step 4, type the level used for the calibration.
If you are measuring with an accelerometer, the level is given in La which is defined as the acceleration relative 10-6 m/s^2. So for acceleration, the reference is 10-6 m/s2 and the quantity is named La. If the level of your vibration device is measured in m/s^2, it can be coverted to dB using this formula:
If you are measuring displacement then no reference is used, type in the level in RMS meters.
Velocity: The reference is 10-9 m/s and the quantity is named Lv.
Force: The reference is 10-6 Newton and the quantity is named Lf.
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