diff --git a/.DS_Store b/.DS_Store
new file mode 100644
index 0000000..5008ddf
Binary files /dev/null and b/.DS_Store differ
diff --git a/microWakeWord_training_notebook.ipynb b/microWakeWord_training_notebook.ipynb
index 5fe2110..b848e8b 100644
--- a/microWakeWord_training_notebook.ipynb
+++ b/microWakeWord_training_notebook.ipynb
@@ -232,7 +232,7 @@
    },
    "outputs": [],
    "source": [
-    "# Generate a large number of wake word samples for training\n",
+    "# Generate a large number of wake word samples for training (with length-scale sweep)\n",
     "import sys, subprocess\n",
     "from pathlib import Path\n",
     "\n",
@@ -240,14 +240,21 @@
     "MODELS_DIR = REPO_DIR / \"models\"\n",
     "MODEL_NAME = \"en_US-libritts_r-medium.pt\"\n",
     "\n",
+    "MAX_SAMPLES = 50000\n",
+    "BATCH_SIZE = 100\n",
+    "\n",
+    "# Piper \"speed\" control via piper-sample-generator is length_scale(s)\n",
+    "LENGTH_SCALES = [\"0.85\", \"0.95\", \"1.00\", \"1.05\", \"1.15\"]\n",
+    "\n",
     "cmd = [\n",
     "    sys.executable,\n",
     "    str(REPO_DIR / \"generate_samples.py\"),\n",
     "    TARGET_WORD,\n",
     "    \"--model\", str(MODELS_DIR / MODEL_NAME),\n",
-    "    \"--max-samples\", \"50000\",\n",
-    "    \"--batch-size\", \"100\",\n",
+    "    \"--max-samples\", str(MAX_SAMPLES),\n",
+    "    \"--batch-size\", str(BATCH_SIZE),\n",
     "    \"--output-dir\", \"generated_samples\",\n",
+    "    \"--length-scales\", *LENGTH_SCALES,\n",
     "]\n",
     "\n",
     "print(\"→\", \" \".join(cmd))\n",