A useful model for creating ScriptableObject directories in Unity. This makes it easy to create an asset that stores AudioClips, Sprites, and other sets of data you want to be able to reference in many places throughout your project. Can be accessed like a Dictionary[string]. I use many variations of this in all my Unity projects.

AudioDirectory.cs

using System.Collections.Generic;
using UnityEngine;

namespace Util.Directories
{
    [CreateAssetMenu(fileName = "AudioDirectory", menuName = "Directory/Audio Directory", order = 1)]
    public class AudioDirectory : ScriptableObject
    {
        public Wrapper[] Directory;

        private Dictionary<string, AudioClip> _dictionary;

        void OnEnable()
        {
            CreateDictionaryIfDoesNotExist();
        }

        private void CreateDictionaryIfDoesNotExist()
        {
            if (_dictionary != null) 
                return;
            
            _dictionary = new Dictionary<string, AudioClip>();
        
            foreach (Wrapper acw in Directory)
                _dictionary.Add(acw.Name,acw.AudioClip);
        }

        /// <summary>
        /// Use this accessor to get the desired clip from other classes
        /// audioDirectory["shoot"]
        /// </summary>
        /// <param name="key"></param>
        public AudioClip this[string key] => _dictionary.ContainsKey(key) ? _dictionary[key] : null;

        /// <summary>
        /// This wrapper allows you to specify audioclips from the inspector.  System.Collections.Generic Dictionary is not
        /// serializable.
        /// </summary>
        [System.Serializable]
        public struct Wrapper
        {
            public string Name;
            public AudioClip AudioClip;
        }
    }
}