diff --git a/Sources/Model/Album.cs b/Sources/Model/Album.cs
index 32a57eb..323ddb0 100644
--- a/Sources/Model/Album.cs
+++ b/Sources/Model/Album.cs
@@ -15,7 +15,7 @@
             }
         }
 
-        private string name;
+        private string name = "Unknown";
 
         public string Description
         {
@@ -30,9 +30,17 @@
             }
         }
 
-        private string description;
+        private string description = "";
 
-        public IEnumerable<Title> Titles { get; set; }
+        public IEnumerable<Title> Titles
+        {
+            get
+            {
+                return titles;
+            }
+        }
+
+        private List<Title> titles = new List<Title>();
 
         public string ImageURL
         {
@@ -47,16 +55,16 @@
                 }
                 if (value.Contains(' '))
                 {
-                    imageURL = value.Replace(' ', '\\');
+                    imageURL = value.Replace(' ', '_');
                 }
-                if (value.Contains('.'))
+                else if (value.Contains('.'))
                 {
                     imageURL = value;
                 }
             }
         }
 
-        private string imageURL;
+        private string imageURL = "unknown.png";
 
         public Artiste Artist { get; set; }
 
@@ -73,7 +81,7 @@
             }
         }
 
-        private string information;
+        private string information = "";
 
         public Album(string name, string file_Name, Artiste artist, string description, string information)
         {
@@ -82,20 +90,16 @@
             Artist = artist;
             Description = description;
             Information = information;
-            Titles = new List<Title>();
         }
 
         public void AddTitle(Title title)
         {
-            Titles.Prepend(title);
+            titles.Add(title);
         }
 
         public void RemoveTitle(Title title)
         {
-            foreach(var item in Titles)
-            {
-                Titles = Titles.Where(item => item != title).ToList();
-            }
+            titles.Remove(title);
         }
 
     }
diff --git a/Sources/Model/Artiste.cs b/Sources/Model/Artiste.cs
index bcab081..ab29d82 100644
--- a/Sources/Model/Artiste.cs
+++ b/Sources/Model/Artiste.cs
@@ -17,16 +17,23 @@ public class Artiste
 
     private string name = "Unknown";
 
-    public IEnumerable<Album> Albums { get; set; }
+    public IEnumerable<Album> Albums
+    {
+        get
+        {
+            return albums.ToList();
+        }
+    }
+
+    private List<Album> albums = new List<Album>();
 
     public Artiste(string name)
     {
         Name = name;
-        Albums = new List<Album>();
     }
 
     public void AddAlbum(Album album)
     {
-        Albums.Prepend(album);
+        albums.Add(album);
     }
 }
diff --git a/Sources/Model/CustomTitle.cs b/Sources/Model/CustomTitle.cs
index 9b41237..e3639c5 100644
--- a/Sources/Model/CustomTitle.cs
+++ b/Sources/Model/CustomTitle.cs
@@ -1,4 +1,6 @@
-namespace Model;
+using System.Runtime.CompilerServices;
+
+namespace Model;
 
 public class CustomTitle : Title { 
 
@@ -15,7 +17,7 @@ public class CustomTitle : Title {
         }
     }
 
-    private string path;
+    private string path = "unknown.mp3";
 
     public CustomTitle(string name, string imageURL, string information, string path) : base(name, imageURL, information)
     {
diff --git a/Sources/Model/Playlist.cs b/Sources/Model/Playlist.cs
index 97d3e43..a3882d0 100644
--- a/Sources/Model/Playlist.cs
+++ b/Sources/Model/Playlist.cs
@@ -15,7 +15,7 @@ public class Playlist
         }
     }
 
-    private string name;
+    private string name = "unknown";
 
     public string Description
     {
@@ -30,9 +30,17 @@ public class Playlist
         }
     }
 
-    private string description;
+    private string description = "";
 
-    public IEnumerable<Title> Morceaux { get; set; }
+    public IEnumerable<Title> Titles
+    {
+        get
+        {
+            return titles;
+        }
+    }
+
+    private List<Title> titles = new List<Title>();
 
     public string ImageURL
     {
@@ -40,31 +48,39 @@ public class Playlist
 
         set
         {
-            if (value != null && value.Contains('.'))
+            if (value == null || !value.Contains('.'))
+            {
+                value = "none.png";
+                imageURL = value;
+            }
+            if (value.Contains(' '))
+            {
+                imageURL = value.Replace(' ', '_');
+            }
+            else if (value.Contains('.'))
             {
                 imageURL = value;
             }
         }
     }
 
-    private string imageURL;
+    private string imageURL = "none.png";
 
     public Playlist(string nom, string description, string imageURL)
     {
         Name = nom;
         Description = description;
-        Morceaux = new List<Title>();
-        this.imageURL = imageURL;
+        ImageURL = imageURL;
     }
 
     public void AddTitle(Title morceau)
     {
-        Morceaux.Prepend(morceau);
+        titles.Add(morceau);
     }
 
     public void RemoveTitle(Title morceau)
     {
-        Morceaux.ToList().Remove(morceau);
+        titles.Remove(morceau);
     }
 
 }
diff --git a/Sources/Model/Title.cs b/Sources/Model/Title.cs
index 1d985e8..b7782d2 100644
--- a/Sources/Model/Title.cs
+++ b/Sources/Model/Title.cs
@@ -15,7 +15,7 @@
             }
         }
 
-        private string name;
+        private string name = "unknown";
 
         public string ImageURL
         {
@@ -23,14 +23,23 @@
 
             set
             {
-                if (value != null && value.Contains('.'))
+                if (value == null || !value.Contains('.'))
+                {
+                    value = "none.png";
+                    imageURL = value;
+                }
+                if (value.Contains(' '))
+                {
+                    imageURL = value.Replace(' ', '_');
+                }
+                else if (value.Contains('.'))
                 {
                     imageURL = value;
                 }
             }
         }
 
-        private string imageURL;
+        private string imageURL = "unknown.png";
 
         public string Information
         {
@@ -45,7 +54,7 @@
             }
         }
 
-        private string information;
+        private string information = "";
 
         public Title(string nom, string file_Name, string informations)
         {
diff --git a/Sources/TestUnitaires/TU_Artiste.cs b/Sources/TestUnitaires/TU_Artiste.cs
index 4b24884..6d29157 100644
--- a/Sources/TestUnitaires/TU_Artiste.cs
+++ b/Sources/TestUnitaires/TU_Artiste.cs
@@ -13,7 +13,8 @@ namespace TestUnitaires
         [InlineData("Hugo TSRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRR")]
         public void TU_Attributes(string name)
         {
-            Assert.True(name != null && name.Length < 75);
+            Artiste a = new Artiste(name);
+            Assert.True(a.Name != null && a.Name.Length < 75);
         }
 
         [Theory]
@@ -23,11 +24,12 @@ namespace TestUnitaires
         public void TU_Methods(string name)
         {
             Artiste a = new Artiste(name);
+
             Album a1 = new Album("Fenêtre sur Rue", "album2. jpg", a, "Un banger", "Sortie : 2012");
-            List<Album> verif = new List<Album>();
-            verif.Add(a1);
+
             a.AddAlbum(a1);
-            Assert.True(a.Albums ==  verif);
+
+            Assert.Contains(a1, a.Albums);
 
         }
     }
diff --git a/Sources/TestUnitaires/TU_Playlist.cs b/Sources/TestUnitaires/TU_Playlist.cs
index f1ca0d0..6a4d78c 100644
--- a/Sources/TestUnitaires/TU_Playlist.cs
+++ b/Sources/TestUnitaires/TU_Playlist.cs
@@ -16,10 +16,11 @@ namespace TestUnitaires
         [InlineData("Sons Soirées", "red-sky .png", "Contient les sons que je mets quand je suis en soirée.")]
         public void TU_Attributes(string name, string url, string desc)
         {
-            Assert.True(name != null && name.Length < 75);
-            Assert.True(url != null && url.Contains('.'));
-            Assert.False(url.Contains(' '));
-            Assert.True(desc != null && desc.Length < 500);
+            Playlist p = new Playlist(name, desc, url);
+            Assert.True(p.Name != null && p.Name.Length < 75);
+            Assert.True(p.ImageURL != null && p.ImageURL.Contains('.'));
+            Assert.False(p.ImageURL.Contains(' '));
+            Assert.True(p.Description != null && p.Description.Length < 500);
         }
     }
 
diff --git a/Sources/TestUnitaires/TU_Title.cs b/Sources/TestUnitaires/TU_Title.cs
index d5162c3..c22de93 100644
--- a/Sources/TestUnitaires/TU_Title.cs
+++ b/Sources/TestUnitaires/TU_Title.cs
@@ -16,10 +16,11 @@ namespace TestUnitaires
         [InlineData("Trajectoire", "morceau1. png", "Sortie : 2020")]
         public void TU_Attributes(string name, string url, string info)
         {
-            Assert.True(name != null && name.Length < 75);
-            Assert.True(url != null && url.Contains('.'));
-            Assert.False(url.Contains(' '));
-            Assert.True(info != null && info.Length < 500);
+            Title t = new Title(name, url, info);
+            Assert.True(t.Name != null && t.Name.Length < 75);
+            Assert.True(t.ImageURL != null && t.ImageURL.Contains('.'));
+            Assert.False(t.ImageURL.Contains(' '));
+            Assert.True(t.Information != null && t.Information.Length < 500);
         }
     }