Dolby Laboratories DP570 - Manual (Page 80)

68 Dolby ® DP570 Multichannel Audio Tool User’s Manual
Configuring a Monitor System Calibrating Speaker Playback Levels
• For music mixing, each speaker channel should be set to the same SPL (the same as
television mixing). There is no standard practice for reference levels for music mixing.
Some engineers prefer to mix louder than others do, but if the levels between channels
are correct, the overall level is not as important.
When mixing for television or music in small mixing rooms such as remote recording
trucks, the Surround channel is generally set 2 dB lower than the front channels. This takes
into account the short distance to the Surround speakers. Experience has shown that this
setting makes the sound in the home environment very close to the sound heard by the
mixer.
A.3.5 Generating Test Noise
The DP570 generates two kinds of test noise: pink and filtered. Pink noise exerts an equal
sound pressure level across the entire spectrum. Filtered noise is pink noise that has been
highpass filtered at the preestablished LFE crossover frequency.
Click a button to generate the appropriate kind of test noise. Click Pink if your bass
management setting is None. Otherwise, click Filtered. The test noise buttons are shown
in Figure A‐2 directly under the Analog Outputs check box.
When activated, the test noise cycles around the speakers in order: Left, Center, Right,
Right Surround, Back Surround Right, Back Surround Left, Left Surround, and Subwoofer
—remaining two seconds at each output before moving onto the next.
The test noise feature is intelligent. When you begin an individual speaker trim adjustment,
the test noise remains at that speaker until you complete the adjustment and move to
another speaker, allowing you to adjust the SPL according to the following procedure.
A.3.6 Increasing the System Volume
After turning on the noise, raise the master Volume slider slowly until meter readings
reach your target SPL. When the system is properly calibrated, this target SPL will register
0 on the master
Volume scale. If it does not, adjust the Master Trim slider until the target
SPL measures 0 on the master Volume slider. You are now ready to begin making fine
adjustments.
Warning: Before you turn on test noise, be sure that your playback system is set no higher
than moderate volume. If the playback level is high, you risk damaging your
speakers and possibly your hearing. The default test noise level from the DP570
is –20 dBFS to the digital outputs (+4 dBu to the analog monitor outputs).