diff -r e046ae3e9628 Lib/wave.py
--- a/Lib/wave.py	Thu Oct 17 12:48:32 2013 +0300
+++ b/Lib/wave.py	Thu Oct 17 21:48:23 2013 +0300
@@ -80,7 +80,7 @@
 
 WAVE_FORMAT_PCM = 0x0001
 
-_array_fmts = None, 'b', 'h', None, 'l'
+_array_fmts = None, 'b', 'h', None, 'i'
 
 import struct
 import sys
@@ -244,6 +244,7 @@
             import array
             chunk = self._data_chunk
             data = array.array(_array_fmts[self._sampwidth])
+            assert data.itemsize == self._sampwidth
             nitems = nframes * self._nchannels
             if nitems * self._sampwidth > chunk.chunksize - chunk.size_read:
                 nitems = (chunk.chunksize - chunk.size_read) // self._sampwidth
@@ -433,6 +434,7 @@
         if self._sampwidth > 1 and sys.byteorder == 'big':
             import array
             data = array.array(_array_fmts[self._sampwidth], data)
+            assert data.itemsize == self._sampwidth
             data.byteswap()
             data.tofile(self._file)
             self._datawritten = self._datawritten + len(data) * self._sampwidth