He spoke in a loud voice.
i-adjective
Used for sounds, especially voices. Often appears as 大きい声.
テレビの音が大きい。
The TV volume is loud.
i-adjective
Abstract use for matters of importance, influence, or value. Common in phrases like 大きい問題 or 大きい意味.
これはとても大きい問題だ。
This is a very important issue.
i-adjective
Used for age, especially when comparing siblings or describing maturity. Often in the form 大きい方 or 大きい子.
大きいお兄ちゃんが手伝ってくれた。
My older brother helped me.