User guide

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CHAPTER 7
Using SIM 3
7.13.2. Check Noise
The following procedure is used to check the noise floor. This is the step-by-step procedure
as presented in SIM 3.
First, select the device under test — Console, Processor, Speaker.
7.13.2.1. Measure Noise Floor — Console, Processor, or Room
1. Select the Band Spectrum measurement. Select the Console, Processor, or Room view.
2. Set the Generator to Off. Select Settings > Spectrum Settings and set Time Weighting
to Accumulate. Wait until the averaging has stabilized the noise measurement.
3. Acquire the Noise Value by selecting Data > Store DataGroup. Enter the settings of the
device that produced this noise level in the Notes field and click Store.
7.13.3. Check Max Output
The following procedure is used to measure the maximum output level at each measurement
point in a branch. Use this method to adjust levels to achieve the best measurement
accuracy. This is the step-by-step procedure as presented in SIM 3.
First, select the device under test — Console, Processor, Speaker.
7.13.3.1. Measure Maximum Output Level — Console, Processor, Speaker/Room
1. Select the Line Spectrum measurement. Select the Console, Processor, or Room view.
Select Settings > Spectrum Settings, and set the Time Weighting to Slow. Set the
Generator to Sine.
2. Then select the frequency and level on the front panel of the SIM-3022 analyzer.
Adjust the frequency controls until the desired frequency has been obtained. Raise the
Generator level to maximum level before the onset of clipping. Adjust input gains to
maximum level before overload to achieve best measurement accuracy.
3. Acquire the maximum output value by selecting Data > Store DataGroup. Store a
DataGroup, noting the maximum level before overload and entering the settings of the
device under test in the Notes field.
7.13.4. Verify Polarity
This procedure is used to verify the polarity of the devices at each measurement point.
Maintaining the polarity within the sound reinforcement system is critical to the proper and
predictable behavior of the system. This is the step-by-step procedure as presented in SIM 3.
Select device under test — Processor, Speaker (Delay Finder method).