Here are some demo tracks for phantom center tonality correction, crosstalk reduction and immersive filters. These demos do not require acoustic measurements.
You just need to download the original files and modified versions closest to your actual listening angle
Here is the modified versions naming convention
You can experiment with your speaker positions and try configurations with lower angle than the 60° standard (image stability will improve)
20°
30°
40°
50°
60°
70°