Phonaudoscope or Phoneidoscope: How To spell?

The word Phonaudoscope is misspelled against Phoneidoscope, a noun meaning "An instrument for studying the motions of sounding bodies by optical means. It consists of a tube across the end of which is stretched a film of soap solution thin enough to give colored bands, the form and position of which are affected by sonorous vibrations."

Word contains consecutive vowels 'EI' in between alphabets phon & doscope is misspelled as 'AU'
Wrong Spelling:  phon-au-doscope 
Correct Spelling:  phon-ei-doscope 
Check more misspelled words of Phoneidoscope to spell it correct.