MAPP Online Tutorial
- Step 1: Place a Loudspeaker
- Click "Configure" then "Insert Loudspeaker...". The "Insert Loudspeaker"
dialog box will appear. You may edit the properties of the loudspeaker
in this dialog box, but for now just press OK; it will default to a
reasonable place.
- Step 2: Predict the Sound Field
- Click the "Predict" button in the tool bar at the top left of the
program. Notice the drop-box next to predict which displays the frequency
125Hz. MAPP Online is now contacting the computational server at Meyer
Sound Laboratories to predict the sound field at that frequency. In
a few moments an image will be displayed in the sound field. This image
represents the sound level in the octave band centered on 125Hz, at
all points in the sound field. Dark red represents the loudest, and
dark blue the quietest. The precise relationship between color and sound
level in dB is displayed on the colorbar to the right of the sound field.
- Step 3: Change the Center Frequency
- Note the table at the bottom of the sound field that reports various
parameters that were used for this prediction. The center frequency
listed in this table is the frequency that was used for whatever currently
appears in the sound field. Now click on the frequency drop-box at the
top of the program next to the Predict button and select a different
frequency. The frequency displayed in the frequency drop-box always
displays the frequency that will be used the next time the Predict button
is pressed. You could press the predict button now if you like, but
you might as well go to the next step and place a microphone as well.
- Step 4: Place a Microphone
- Click "Configure" then "Insert Microphone...". The "Insert Microphone"
dialog box will appear. You may edit the properties of the microphone
in this dialog box, but for now just press OK; it will default to a
reasonable place.
- Step 4: Predict the Sound Field and Virtual SIM response
- Press the Predict button, and wait briefly for results from the Meyer
Sound Computational server to return. The Virtual SIM window will come
forward and display the Third Octave Band Spectrum prediction at the
microphone location. Note the table at the bottom of the Virtual SIM
window. The A-Weighted average and peak SPL are reported there; the
full-spectrum average and peak SPL are also reported there when they
are available.
- Step 5: View the Impulse Response
- In the Virtual SIM window, click "Measurement" then "Impulse Response".
The predicted impulse response is displayed. The "peak impulse" in the
table displays the arrival time of the maximum peak. This value is used
in conjunction with the estimated sound speed to compute the "approximate
distance" from the microphone to the loudspeaker(s) also reported in
the table.
- Step 6: View the Frequency Response
- In the Virtual SIM window, click "Measurement" then "Frequency Response".
The predicted frequency response is displayed.
- Step 7: Use the VX-1 program equalizer
- Click the "VX-1 Program Equalizer" button in the tool bar at the top
left of the Virtual SIM window. The "VX-1" dialog box will appear. Move
the dialog box so that you can see the frequency response behind it.
When you change the parameters of the VX-1 a green line will be displayed
in the frequency response which represents the 1/EQ curve. By matching
the 1/EQ curve to the frequency response you have found the VX-1 settings
that will equalize your loudspeaker(s). This is explained in greater
detail in the Acoustical
Information help page.
- Step 8: Insert a Loudspeaker Array
- Click on the sound field window to bring it to the front. Notice that
the sound field has changed to represent the new frequency you chose
in Step 3. Click on the loudspeaker you inserted to select it, and then
click "Edit" then "Delete" to erase the loudspeaker and clear the sound
field. The sound field is blanked whenever you add or remove a loudspeaker.
Now click "Configure" then "Insert Loudspeaker Array..." and a dialog
box will appear. Click the "Array Type" drop-box at the top of the
dialog and choose type of loudspeaker array you would like. Now look
at the table at the bottom of the dialog box. Click on one of the
loudspeaker names in the first column, a drop box will appear where
you can choose the model name of that loudspeaker in the array (i.e.
when the array type is "M1D" you may select either M1D or M1DSub).
Now click on one of the cells in the second column. Here you can edit
the relative angle between that loudspeaker and the loudspeaker above
it. Click OK to close the dialog box, and then Predict.
- Step 9: Save your configuration
- Click "File" then "Save" to save your configuration so you can bring
it back and edit it later.
- Step 9: Save a Web Page of your Prediction
- Click "File" then "Save as Webpage" and enter a file name. A webpage
will be generated which includes images of the sound field prediction,
the three Virtual SIM panels, and a list of your loudspeakers, microphones,
and other properties.
Help Contents
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Help Contents
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