revert bitrate conversion scale to match mp3 encoder

emissions/management/commands/create-sound-files.py

@@ -123,23 +123,24 @@ class Command(BaseCommand):
         vorbis_rates = [64, 80, 96, 112, 128, 160, 192, 224, 256, 320, 500]
         orig_bitrate = get_bitrate(soundfile.file.path)
         vorbis_q = 5
-        mp3_q = 4
         if orig_bitrate is not None:
             if soundfile.episode.emission.podcast_sound_quality == 'high':
                 vorbis_q = 9
-                mp3_q = 9
             # cap quality to original bitrate (using vorbis quality mapping)
             for i, rate in enumerate(vorbis_rates):
                 if orig_bitrate < rate:
                     vorbis_q = min((i, vorbis_q))
-                    mp3_q = min((i, mp3_q))
                     break
 
         cmd = ['ffmpeg', '-y', '-i', soundfile.file.path]
         if format == 'ogg':
             cmd.extend(['-q:a', str(vorbis_q)])
         elif format == 'mp3':
-            cmd.extend(['-q:a', str(mp3_q)])
+            mp3_q = 9 - vorbis_q
+            if mp3_q == 0:
+                cmd.extend(['-b:a', '320k'])
+            else:
+                cmd.extend(['-q:a', str(mp3_q)])
 
         cmd.append(file_path)