Rig It, Measure It, Align It!

The SIM 3 system’s unique ability to calculate and display all three transfer functions at the same time makes access to important data easy. By using any two of three measurement points, you can analyze a single component or a complete sound system. In addition, up to four memory traces can be displayed, enabling a quick comparison of measurements.

Multiple overlayed memory traces allow for comparison and crossover adjustments.

In addition to the frequency and phase response measurements SIM 3 allows you to do other amplitude and time-related meaningful measurements.

Band and Line Spectrum: Amplitude vs. Frequency

The Band Spectrum measurement calculates the spectral content of each point in the system — console output, processor output and microphone, and displays them individually or simultaneously. The ANSI 1/3 octave displays allow you to do calibrated measurements or help you quickly verify signal presence throughout the system. SIM 3 can concurrently display both peak and average readings. Microphone measurements can be displayed in a linear or A, B, or C-weighted SPL calibrated scales.

The high resolution Band Spectrum displays console, processor and mic frequency spectra on a single screen.

Optimized for sine wave stimulus, SIM 3’s Line Spectrum measurement can be used for distortion analysis down to .001% THD. SIM 3's high-quality preamps allow it to measure the noise floor of system components. Signal verification is instantaneous, overall frequency content of the signal being used is obvious, and distortion components are summed and displayed as a percentage relative to the amplitude at the cursor position. This makes amplitude vs. frequency and harmonic distortion analysis quick and simple.

In Spectrum view, using a sine wave as test signal, you can see the fundamental plus harmonics, while calculating THD.

Delay Finder: Time vs. Energy

The Delay Finder function has many uses:

• Identifies the propagation delay from the loudspeaker to the microphone and internally synchronizes signals in time to enable accurate calculation of transfer functions.
• Identifies the differing arrival times of the direct sound and sounds from other loudspeaker in the system. This time vs. energy display helps to identify problems in the time domain and gives you information to solve them by adding the correct amount of delay to synchronize the loudspeaker system.
• Identifies the differing arrival times of the direct sound and reflections in the room from floor, ceiling walls etc. This time vs. energy display helps to identify problems in the time domain and gives you information to solve them by re-aiming the loudspeakers and/or possibly using absorptive materials in the room.

In addition, Delay Finder identifies the latency delay in digital signal processors and internally synchronizes signals in time to enable accurate calculation of transfer functions between points in the system with time differences. Delay Finder will even show you polarity information to help locate miswired loudspeakers and electronic components that are reversed in polarity from the rest of the system.

Delay Finder internally synchronizes signals in time to enable accurate calculation of transfer functions, including compensation for acoustical propagation delay.

Understanding the acoustical environment and determining optimal loudspeaker placement has never been easier. The Set System Delay procedure gives you the information to set delay times for proper synchronization of all loudspeakers in a system.

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