Welcome to the PSR Tutorial Forum, mtrigoboff!
With "Soft 2" you can reach a high volume with the lightest possible playing strength. Also see the attached screenshot (taken from page 37 in the SX900/700 Reference Manual V1.10).
P.S.
In "Voice Edit > Common" (on the SX900/700) or "Voice Set > Common" (on the SX600) you can increase the volume of voices if necessary (if volume 127 in the Mixer is still too low). You can also adjust the Touch Sensitivity parameters "Depth" and/or "Offset" here if required. In this way, too, a higher volume can be achieved if required.
Best regards,
Chris
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