diff --git a/node-server/assets/script.js b/node-server/assets/script.js
index 071dd8c..8238a91 100644
--- a/node-server/assets/script.js
+++ b/node-server/assets/script.js
@@ -12,10 +12,13 @@ const loopBtn = document.getElementById('loop');
 let isPlaying = false;
 let isLooping = false;
 let idleTimeout = null;
+let reverseInterval = null;
+
+// 3. Variables pour calcul de vitesse
 let lastPosition = null;
 let lastTime = null;
 
-// 3. Connexion Socket.io
+// 4. Connexion Socket.io
 const socket = io();
 
 socket.on('position', (position) => {
@@ -24,19 +27,24 @@ socket.on('position', (position) => {
   if (lastPosition !== null && lastTime !== null) {
     const deltaPos = position - lastPosition;
     const deltaTime = (now - lastTime) / 1000;
+
     const speed = deltaPos / deltaTime;
+    console.log('instant speed:', speed);
 
     clearTimeout(idleTimeout);
 
-    if (Math.abs(speed) < 10) {
+    if (Math.abs(speed) < 5) {
       stopPlayback();
       return;
     }
 
-    if (speed > 0) {
-      controlForwardPlayback(speed);
+    const isReverse = speed < 0;
+
+    if (isReverse) {
+      simulateReverse(Math.abs(speed));
     } else {
-      controlRewind(Math.abs(speed));
+      stopReverse();
+      controlPlayback(speed);
     }
   }
 
@@ -48,47 +56,7 @@ socket.on('position', (position) => {
   }, 300);
 });
 
-// 4. Fonctions principales
-
-function controlForwardPlayback(speed) {
-  const rate = 1 + speed * 0.0003;
-  const playbackSpeed = Math.min(2, Math.max(0.5, rate));
-
-  vinyl.classList.remove('reverse');
-  vinyl.style.animationPlayState = 'running';
-
-  if (!isPlaying) {
-    audio.play();
-    isPlaying = true;
-  }
-
-  audio.playbackRate = playbackSpeed;
-}
-
-function controlRewind(speed) {
-  if (isPlaying) {
-    audio.pause();
-    isPlaying = false;
-  }
-
-  const rewindAmount = Math.min(speed * 0.01, 1);
-  audio.currentTime = Math.max(0, audio.currentTime - rewindAmount);
-
-  vinyl.classList.add('reverse');
-  vinyl.style.animationPlayState = 'running';
-}
-
-function stopPlayback() {
-  if (isPlaying) {
-    audio.pause();
-    isPlaying = false;
-  }
-
-  vinyl.classList.remove('reverse');
-  vinyl.style.animationPlayState = 'paused';
-}
-
-// 5. Fonctions interface
+// 5. Fonctions
 
 function togglePlay() {
   if (isPlaying) {
@@ -120,7 +88,67 @@ function setProgress(e) {
   audio.currentTime = (clickX / width) * duration;
 }
 
-// 6. Événements manuels
+// Lecture en avant selon la vitesse
+function controlPlayback(speed) {
+  stopReverse();
+
+  if (speed > 0) {
+    if (!isPlaying) {
+      audio.play();
+      vinyl.style.animationPlayState = 'running';
+      isPlaying = true;
+    }
+
+    // Vitesse normalisée
+    const normalized = Math.min(speed / 100, 1);
+    const minRate = 0.3;
+    const maxRate = 1.5;
+    const playbackSpeed = minRate + (maxRate - minRate) * normalized;
+
+    audio.playbackRate = playbackSpeed;
+    vinyl.style.animationDuration = `${1 / playbackSpeed * 2}s`;
+    vinyl.style.animationDirection = 'normal';
+  }
+}
+
+function stopPlayback() {
+  audio.pause();
+  vinyl.style.animationPlayState = 'paused';
+  isPlaying = false;
+  stopReverse();
+}
+
+function simulateReverse(speed) {
+  const reverseSpeed = Math.min(speed * 0.01, 2); // secondes à reculer par tick
+
+  if (!reverseInterval) {
+    reverseInterval = setInterval(() => {
+      if (audio.currentTime > 0.05) {
+        audio.currentTime -= reverseSpeed * 0.1;
+        vinyl.style.animationPlayState = 'running';
+        vinyl.style.animationDirection = 'reverse';
+      } else {
+        stopPlayback();
+      }
+    }, 100);
+
+    if (!isPlaying) {
+      isPlaying = true;
+    }
+  }
+
+  audio.pause(); // son désactivé pour reverse simulé
+}
+
+function stopReverse() {
+  if (reverseInterval) {
+    clearInterval(reverseInterval);
+    reverseInterval = null;
+    vinyl.style.animationDirection = 'normal';
+  }
+}
+
+// 6. Événements
 
 vinyl.addEventListener('click', togglePlay);
 audio.addEventListener('timeupdate', updateProgress);