diff --git a/assets/js/creations/pattern/pattern_audio.js b/assets/js/creations/pattern/pattern_audio.js
index 119612af..12904b50 100755
--- a/assets/js/creations/pattern/pattern_audio.js
+++ b/assets/js/creations/pattern/pattern_audio.js
@@ -12,6 +12,9 @@ import { SuperSaw } from "../../audio/plugins/SuperSaw.js";
 import { Lb302 } from "../../audio/plugins/Lb302.js";
 import { Kicker } from "../../audio/plugins/Kicker.js";
 
+const TICKS_PER_STEP = 12; // LMMS: 12 ticks por 1/16
+const STEPS_PER_BAR = 16;  // 4/4 em 1/16
+
 // Mapa para facilitar a criação dinâmica
 const PLUGIN_CLASSES = {
   tripleoscillator: TripleOscillator,
@@ -310,9 +313,21 @@ function schedulePianoRoll() {
         }
       }, events).start(0);
 
-      const bars = parseInt(document.getElementById("bars-input")?.value || 1);
+      // calcula até onde vai a última nota do pianoroll
+      let maxEndTick = 0;
+      for (const n of pattern.notes) {
+        const pos = Number(n.pos) || 0;
+        const rawLen = Number(n.len) || 0;
+        const len = rawLen < 0 ? TICKS_PER_STEP : rawLen;
+        maxEndTick = Math.max(maxEndTick, pos + Math.max(len, TICKS_PER_STEP));
+      }
+
+      const totalStepsNeeded = Math.max(1, Math.ceil(maxEndTick / TICKS_PER_STEP));
+      const barsNeeded = Math.max(1, Math.ceil(totalStepsNeeded / STEPS_PER_BAR));
+
       part.loop = true;
-      part.loopEnd = bars + "m";
+      part.loopEnd = `${barsNeeded}m`;
+
 
       activeParts.push(part);
     }