How to keep the same power (sonority) between pure sines?
From the comments on the question I gather that you want the individual sine waves to appear to be at the same volume. Unfortunately, there is no single EQ setting you could apply to achieve this. As for the reasons, let's look at the equal-loudness contours:


Source

What these contours tell us is that for a specific level of phones there exists an EQ setting that would make your sine waves sound at equal loudness. Unfortunately, the human perception of loudness not only depends on frequency but also on SPL—what that means is that your EQ settings that you meticulously set up for a certain level of phones won't work any more if you change the overall gain of your playback system. To compensate for the SPL-dependency of the human hearing you would need an adaptive EQ that takes into consideration the SPL of the signal at 1000 Hz (or any other reference frequency) by measureing it with a sound level meter and setting the EQ parameters accordingly.