diff --git a/whisper_online.py b/whisper_online.py
index 26fe6db..266fc72 100644
--- a/whisper_online.py
+++ b/whisper_online.py
@@ -23,15 +23,19 @@ def load_audio_chunk(fname, beg, end):
 
 class ASRBase:
 
-    # join transcribe words with this character (" " for whisper_timestamped, "" for faster-whisper because it emits the spaces when neeeded)
-    sep = " "
+    sep = " "   # join transcribe words with this character (" " for whisper_timestamped,
+                # "" for faster-whisper because it emits the spaces when neeeded)
 
     def __init__(self, lan, modelsize=None, cache_dir=None, model_dir=None):
         self.transcribe_kargs = {}
         self.original_language = lan 
 
+        self.import_backend()
         self.model = self.load_model(modelsize, cache_dir, model_dir)
 
+    def import_backend(self):
+        raise NotImplemented("must be implemented in the child class")
+
     def load_model(self, modelsize, cache_dir):
         raise NotImplemented("must be implemented in the child class")
 
@@ -49,11 +53,14 @@ class ASRBase:
 class WhisperTimestampedASR(ASRBase):
     """Uses whisper_timestamped library as the backend. Initially, we tested the code on this backend. It worked, but slower than faster-whisper.
     On the other hand, the installation for GPU could be easier.
+    """
 
-    If used, requires imports:
+    sep = " "
+    
+    def import_backend(self):
+        global whisper, whisper_timestamped
         import whisper
         import whisper_timestamped
-    """
 
     def load_model(self, modelsize=None, cache_dir=None, model_dir=None):
         if model_dir is not None:
@@ -89,8 +96,12 @@ class FasterWhisperASR(ASRBase):
 
     sep = ""
 
+    def import_backend(self):
+        global faster_whisper
+        import faster_whisper
+
     def load_model(self, modelsize=None, cache_dir=None, model_dir=None):
-        from faster_whisper import WhisperModel
+        #from faster_whisper import WhisperModel
 
 
         if model_dir is not None:
@@ -465,11 +476,11 @@ if __name__ == "__main__":
     #asr = WhisperASR(lan=language, modelsize=size)
 
     if args.backend == "faster-whisper":
-        from faster_whisper import WhisperModel
+        #from faster_whisper import WhisperModel
         asr_cls = FasterWhisperASR
     else:
-        import whisper
-        import whisper_timestamped
+        #import whisper
+        #import whisper_timestamped
     #    from whisper_timestamped_model import WhisperTimestampedASR
         asr_cls = WhisperTimestampedASR