diff --git a/tests/scale_pcm.py b/tests/scale_pcm.py
index b44fa33e04d42d50ac0311e67ce52d281ab24ba5..9aef914da1db574c84c54c0dc7f7d7097691f0ec 100755
--- a/tests/scale_pcm.py
+++ b/tests/scale_pcm.py
@@ -3,6 +3,7 @@
 import os
 import sys
 import argparse
+import pathlib
 
 THIS_PATH = os.path.join(os.getcwd(), __file__)
 sys.path.append(os.path.join(os.path.dirname(THIS_PATH), "../scripts"))
@@ -10,9 +11,16 @@ sys.path.append(os.path.join(os.path.dirname(THIS_PATH), "../scripts"))
 import pyaudio3dtools
 import pyivastest
 import numpy as np
+import concurrent.futures
 
 
-def scale_pcm(file1, file2, factor = 1.0) -> None:
+def scale_folder(folder, factor):
+
+    files = list(folder.glob("*.wav"))
+    with concurrent.futures.ThreadPoolExecutor() as executor:
+        executor.map(scale_file, files, files, [factor] * len(files))
+
+def scale_file(file1, file2, factor = 1.0) -> None:
     """
     Scale file1 to file2
     """
@@ -22,10 +30,9 @@ def scale_pcm(file1, file2, factor = 1.0) -> None:
 
 if __name__ == "__main__":
     parser = argparse.ArgumentParser()
-    parser.add_argument("file1", type=str)
-    parser.add_argument("file2", type=str)
+    parser.add_argument("folder", type=pathlib.Path)
     parser.add_argument("factor", type=float)
     args = parser.parse_args()
 
-    scale_pcm(**vars(args))
+    scale_folder(**vars(args))
     sys.exit(0)