...
[SerializeField] private AudioSource soundSource;
[SerializeField] private AudioClip hitWallSound;      
[SerializeField] private AudioClip hitEnemySound;    
...
if (target != null) {          
    target.ReactToHit();
    soundSource.PlayOneShot(hitEnemySound);  
} else {
    StartCoroutine(SphereIndicator(hit.point));
    soundSource.PlayOneShot(hitWallSound); 
}
...
