While designing his recording studio, Brian was trying to determine what type of surface he should use for his studio walls. He wanted to be able to produce clear, crisp, sound. So he needed a surface that wouldn't cause his music to echo. What type of surface should Brian use for his studio walls?

Acoustic Foam.

Explanation:

Acoustic Foam: This is a kind of material, which is commonly known as it called a Studio Foam, it has a kind of wedge or pyramid shape that plays a big role in absorbing sound. Brian would have to use acoustic foam by placing them round the walls and ceiling as this would stop any echoing sound and in return give a crisp and clear sound when music is been played it the studio.

he would use the colour black