JBL SDP-40 manual Internal Noise Test, Setup, Performing Manual Output Level Calibration

SETUP

JBL

Performing Manual Output Level Calibration

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INTERNAL NOISE TEST

SETUP SPEAKERS MANUAL LEVELS CALIBRATION INTERNAL NOISE TEST

Opens the INTERNAL NOISE message shown on the previous page, which indicates that the internal noise test generates loud calibration noise signals.

When the INTERNAL NOISE message opens:

•	Press the	arrow button to open the SPEAKER LEVEL ADJUST
	menu shown on the previous page. When the SPEAKER LEVEL
	ADJUST menu opens, the internal noise test automatically
	begins.
•	Press the	arrow button to close the message without activating

the internal noise test.

During the internal noise test, the SDP-40 sends calibration noise signals to each speaker in the order shown on the SPEAKER LEVEL ADJUST menu. The cursor automatically scrolls through output level parameters, highlighting each parameter as the SDP-40 sends the calibration noise signal to the corresponding speaker. The calibration noise signal is sent to each speaker for about 4 seconds.

Note:

When the internal noise test begins, the SDP-40 automatically sets volume level to +0dB. Avoid adjusting the master volume level while the test is in progress to achieve THX reference levels (75dB).

To manually calibrate output levels during the internal noise test:

1. Set the SPL meter to “C” weighting and “SLOW” response.

2. Press the and arrow buttons to highlight the desired output level parameter. Then, quickly press the arrow button to select this output level parameter. The horizontal bar graph shown on the previous page will open on the on-screen display and automatic scrolling will stop.

Note:

During the internal noise test, it is possible to select an output level parameter just as the cursor is about to automatically scroll to the next parameter, causing the SDP-40 to send the calibration noise signal to both speakers. If this occurs, reselect the desired speaker.

3. When the horizontal bar graph opens, press the and arrow buttons to select the output level that achieves a 75dB SPL meter reading from the primary listening position.

4.When the desired output level has been selected, press the arrow button to close the parameter. The internal noise test will continue and automatic scrolling will resume.

5.Repeat steps 2, 3, and 4 until all desired output levels have been set.

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