KLING & FREITAG CON:SEQUENZA+K&F - Manual (Page 33)

User’s Guide K&F CON:SEQUENZA+
KLING & FREITAG GmbH Version 1.0 Seite 33 von 53
CON:SEQUENZA+ is using a simplified model of treating combinations of sound sources. Elements
of a line array are always summed in a complex manner, which means that full signal coherence is
assumed. However, multiple line arrays are combined using power summation which is based on a
random-phase assumption.
The first assumption may overestimate pressure summation and cancellation effects among
elements of the array, especially for very tall systems and windy environments. But it has turned
out to be a good approximation in practice. The second assumption will underestimate the level of
coherence among several line arrays, especially at low frequencies or when they have the same
configuration and are placed very close to each other. Nevertheless, for most practical setups this
approximation is feasible.
Absolute SPL calculations in CON:SEQUENZA+ assume a broadband excitation with a signal that is
like program material. You can choose among three different types of input signal, see §3.3. Level
values displayed in the mapping or in the frequency response are sum levels. This representation is
equivalent to the readings one can take from real-time analyzers (RTA) and sound level meters
(SLM).
Note that in CON:SEQUENZA+ each sound source is always driven at its maximum input level. This
means that if you assign a gain of -6 dB to each cabinet of the array, the output SPL will be
unchanged. That is because the maximum input voltage is increased by 6 dB while the sensitivity
of the system is decreased by 6 dB. The only exceptions from this are the Filter and Global Filter
functions. They can be employed to adjust output levels of different arrays relative to each other.
The current input voltage and the maximum input voltage for the selected line array system are
shown in the status bar.
Be aware that the maximum input levels displayed in the software are only estimates based on the
specification and an ideal input signal. Just like the SPL prediction for the receive location these
results should be considered with care and are only accurate under the given limitations and
uncertainties.
Please keep in mind that CON:SEQUENZA+ is just a tool implementing an acceptable compromise
between ease-of-use, calculation speed and accuracy based on its main purpose of use.
3.3 Mapping Options
To access mapping options, select the menu File | Options or hit F9. Then select the Calculation
Parameters list item. Here you can choose the calculation resolution for your mappings: this will
affect the patch size of your calculations. Note that the number of points to be calculated
increases by about 10 times for every resolution level. Lower resolutions are computed first, and
their result displayed while higher resolutions are being processed. You can click on the mapping
progress bar located bottom right of Top View and Side View to read alternatively the remaining
time until the current resolution is completed or the total time until calculations are finished.
On the same page you can also edit the type of input signal to be played from Sound Sources (see
previous paragraph) and the accuracy of calculations (Fast Approximation will compute values with
an internal resolution of 1/3 octave, High Resolution will use an internal resolution of 1/24 octave).