Wayne Parham Messages: 18791 Registered: January 2001
Illuminati (33rd Degree)
Most people put speakers on stands to position them roughly at ear level. I generally recommend putting mains on stands and flanking them with subs. Study on flanking subs to learn more about that configuration.
The angle of the stands serves to "cradle" the speaker, because there is a back plate (or usually just a lip) that the speaker rests on. It doesn't take much tilt to allow gravity to hold them in place. The stands could be flat though, and the speaker could be secured in a different way.
The pattern is clean above and below the forward centerline +/-20° so some vertical tilt is OK. If the speaker is angled upwards, say 5°, then the vertical nulls would be positioned 25° above and 15° below.