No magic focus frequency.

Start is in the working Public V1 target; Focus remains later. Both are framed around beginning, reducing friction and creating a workable environment—not a claim that one sound forces concentration.

Separate mechanism from preference.

Preference

A sound environment may be useful because it masks interruption, creates continuity or is personally preferred. Those are different explanations and should stay different.

Research before copy.

Specific public claims and citations remain gated until the Focus product itself is defined.