Martin Logan subs have a Tone sweep button mentioned in this video.
https://youtu.be/wty1M6GzVt4Good points made above that it would be nice if the SVS app could generate test tones.
Using the tone generator in REW is simple solution.
Is it not more important to use demo material that you are familiar with, so that when you add or take away equipment, you can hear the difference. The most important thing is to keep it consistent. If a demo CD is introducing new content along with new hardware... what’s the point?