Import ogg via script from non assets folder

Hi, I tryng to import some ogg files in runtime using script, and this ogg files is not on assets/unity folders.

The last way i tryed is this:

 using System.Collections;
 using System.Collections.Generic;
 using System.IO;
 using UnityEngine;
 using UnityEngine.UI;
 
 [RequireComponent(typeof(AudioSource))]
 public class GuitarPlayer : MonoBehaviour {
 
     public Text txtGuitarTempo;
     public Text txtGuitarDuration;
     public string musicPath;
 
     public Main main;
     private AudioSource guitarSource;
 
     // Use this for initialization
     void Start () {
         guitarSource = GetComponent<AudioSource>();
         musicPath = main.getMusicPath() + "/guitar.ogg";
 
 
         WWW loader = new WWW("file:///" + musicPath);
 
         guitarSource.clip = loader.GetAudioClip(false, false, AudioType.OGGVORBIS);
         guitarSource.clip.name = "guitar";
 
         txtGuitarDuration.text = "Guitar Duration: "+ System.TimeSpan.FromSeconds(guitarSource.clip.length);
 
         main.SetGuitarPlayer = this;
     }
  
     public void PlayGuitar()
     {
         guitarSource.Play();
     }
 
     public void PauseGuitar()
     {
         if (guitarSource.isPlaying)
         {
             guitarSource.Pause();
         } else
         {
             guitarSource.Play();
         }
     }
 
     public void StopGuitar()
     {
         guitarSource.Stop();
     }
 
     // Update is called once per frame
     void Update () {
         txtGuitarTempo.text = "Guitar Tempo: " + System.TimeSpan.FromSeconds(guitarSource.time);
     }
 }

The most important part is on start. The actual location of that guitar.ogg file is D:/Unity/Projetos/GuitarParty/Guitar Party/Assets/Musics/Teste/guitar.ogg (i known is in assets, but i need to change the file location in runtime)

I doing something wrong is there is other way to import?

Oh, and when i put the file on assets folder and import via unity editor, works fine. The problem is with the way i using to import from other folders :/

Using latest Unity version.