diff --git a/youtube_dl/extractor/soundgasm.py b/youtube_dl/extractor/soundgasm.py
index 5f811444a..f9db15ec9 100644
--- a/youtube_dl/extractor/soundgasm.py
+++ b/youtube_dl/extractor/soundgasm.py
@@ -12,29 +12,26 @@ class SoundgasmIE(InfoExtractor):
                  r'https?://(?:www\.)?soundgasm\.net(?::80)?/u/' + \
                  r'(?P<user>[0-9a-zA-Z_-]+)/(?P<display_id>[0-9a-zA-Z_-]+)'
     _TESTS = [{
-            'url': 'http://soundgasm.net/u/ytdl/Piano-sample',
-            'md5': '010082a2c802c5275bb00030743e75ad',
-            'info_dict': {
-                'id': '88abd86ea000cafe98f96321b23cc1206cbcbcc9',
-                'ext': 'm4a',
-                'title': 'Piano sample',
-                'description': 'Royalty Free Sample Music',
-                'uploader': 'ytdl',
-            }
-        },
-        {
-            'url': 'http://web.archive.org/web/20181218221507/' +
-                   'https://soundgasm.net/u/ytdl/Piano-sample',
-            'md5': '010082a2c802c5275bb00030743e75ad',
-            'info_dict': {
-                'id': '88abd86ea000cafe98f96321b23cc1206cbcbcc9',
-                'ext': 'm4a',
-                'title': 'Piano sample',
-                'description': 'Royalty Free Sample Music',
-                'uploader': 'ytdl',
-            }
+        'url': 'http://soundgasm.net/u/ytdl/Piano-sample',
+        'md5': '010082a2c802c5275bb00030743e75ad',
+        'info_dict': {
+            'id': '88abd86ea000cafe98f96321b23cc1206cbcbcc9',
+            'ext': 'm4a',
+            'title': 'Piano sample',
+            'description': 'Royalty Free Sample Music',
+            'uploader': 'ytdl'
         }
-    ]
+    }, {
+        'url': 'http://web.archive.org/web/20181218221507/https://soundgasm.net/u/ytdl/Piano-sample',
+        'md5': '010082a2c802c5275bb00030743e75ad',
+        'info_dict': {
+            'id': '88abd86ea000cafe98f96321b23cc1206cbcbcc9',
+            'ext': 'm4a',
+            'title': 'Piano sample',
+            'description': 'Royalty Free Sample Music',
+            'uploader': 'ytdl'
+        }
+    }]
 
     def _real_extract(self, url):
         mobj = re.match(self._VALID_URL, url)
@@ -47,7 +44,8 @@ class SoundgasmIE(InfoExtractor):
             'audio URL', group='url')
 
         if mobj.group('archive'):
-            audio_url = audio_url[:41] + "if_" + audio_url[41:]
+            pos = mobj.span('archive')[1] - 1
+            audio_url = audio_url[:pos] + "if_" + audio_url[pos:]
 
         title = self._search_regex(
             r'<div[^>]+\bclass=["\']jp-title[^>]+>([^<]+)',
@@ -82,17 +80,15 @@ class SoundgasmProfileIE(InfoExtractor):
         'info_dict': {
             'id': 'ytdl',
         },
-        'playlist_count': 1,
-        },
+        'playlist_count': 1
+    },
         {
-            'url': 'http://web.archive.org/web/20181218222843/' +
-                   'https://soundgasm.net/u/ytdl',
+            'url': 'http://web.archive.org/web/20181218222843/https://soundgasm.net/u/ytdl',
             'info_dict': {
-                'id': 'ytdl',
+                'id': 'ytdl'
             },
-            'playlist_count': 1,
-        }
-    ]
+            'playlist_count': 1
+    }]
 
     def _real_extract(self, url):
         profile_id = self._match_id(url)