Générateur de Signal

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Configuration des Options du Programme > Générateur de Signal

 

sig-gen-select

 

The signal generator configuration dialog is accessible by clicking on the signal generator readout field in both Real Time and Impulse Response mode. The Smaart 7 signal generator supports for basic signal types; random and pseudorandom  pink noise, single and dual sine waves and file-based data from Windows wave (.wav) or AIFF files. The configuration options for the signal generator differ somewhat depending on the type of signal currently selected.

 

Pink Noise Signals

 

Options for pink noise include Random and Pseudorandom. Pseudorandom noise repeats on intervals that are a power of two samples in length and can be band-limited. Pseudorandom cycle lengths are available to match all the FFT sizes offered in Smaart. In previous versions of Smaart we referred to pseudorandom noise as sync noise because the cycle length was automatically set to match the FFT size in use. In Smaart 7, because there can be multiple FFT sizes in use at any given time, you must explicitly choose the cycle length you wish to use. The program will not attempt to set it for you.

 

For both random and pseudorandom pink noise you can elect to show the output levels as RMS or peak levels. When Show Peak is selected, a given signal level will read 12 dB the higher than when Show RMS is selected. Checking the Band Limited checkbox activates the Start Freq and Stop Freq controls enabling you to specify start and stop frequencies for your desired passband. The Cycle selector specifies the repeat interval for the noise sequence in samples.

 

When Random noise is selected the only options you need to set are the output level and whether you prefer to specify level as a Peak or RMS value. Random noise in Smaart 7 is generated on-the-fly. Technically it is pseudorandom noise as well, however since this generator is randomly seeded every time you run it and once started, it has a cycle length of many billions of years, we feel it is extremely unlikely that it will ever produce exactly the same sequence of samples more than once in practice.

 

Sine and Dual Sine Waves

 

Sine waves and dual sine waves, you can opt to show the output levels as peak or RMS. When Show Peak is selected for a sine wave signal a given signal level will read 3 dB higher then when Show RMS is selected. The frequency and output level of each sine wave are independently selectable. There's also a master output level control that sets the overall output level.

 

File-based Signals

 

In addition to internally generated signals, Smaart also enables you to use any.wav or AIFF file as a test signal. When using file-based signals you just need to select the file you want to use and specify the output level. When the Normalize option is selected,  Smaartwill scale the signal to a peak level of zero dB full scale.