Description:

The basis for correction filters is the pulse response recorded by the LogSweep Recorder. Since this contains a lot of information such as reflections which is unsuitable for filter creation, the pulse response must be processed as the first step. To do this, the frequency response must be smoothed and only the direct sound from the loudspeaker included in the calculation of correction filter by excluding reflections using Frequency Dependent Windowing.

Options:

• Psychoacoustic Response: You can choose between two different smoothing methods - psychoacoustic, or 1/3 sliding octave. Follow the link for an explanation.
• High Frequency Treatment: Since the frequency response drops sharply at high frequencies, smoothing can be more pronounced from this frequency onwards.
• Frequency Dependent Window : Specifies the number of cycles to be included for correction. The first value refers to low frequencies (20Hz) and the second value to high frequencies (20kHz). For example, FDW 15/5 means that 15 cycles of 20Hz and 5 cycles at 20kHz are included in the calculation. Acourate automatically adjusts the time window for frequencies in between.
• FDW Interpolation: Selects the options for interpolation for the number of cycles between low and high frequencies. The options are logarithmic (default) or linear.
• Prefilter: If a prefilter was created by Macro 0, selecting this option will include the prefilter in processing the pulse response.
• Mono / Stereo: by default, Acourate will process the left and right impulse response automatically. If desired, a single impulse response can be processed (for example, if you wish to correct a center channel).

Usage:

Load the left and right impulse responses recorded by the Logsweep Recorder into curves 1 and 2. After setting the options and clicking on “Run Macro 1”, two new files are created. The original files are not overwritten. The files have the extension *mp.dbl to indicate that the minimum phase version has been created.

Examples: