How Talkies Talk

Genre: <a href="https://fmovies-to.lol/genre/99/documentary" style="color:#d9d9d9;" onmouseover="this.style.color='#00acc2';" onmouseout="this.style.color='#d9d9d9';">Documentary
Director: Donald Carter
Cast: <a href="/actor/1702942/noel-birkin" style="color:#d9d9d9;" onmouseover="this.style.color='#00acc2';" onmouseout="this.style.color='#d9d9d9';">Noel Birkin
Country: <a href="/country/gb" style="color:#d9d9d9;" onmouseover="this.style.color='#00acc2';" onmouseout="this.style.color='#d9d9d9';">United Kingdom

Documentary explaining how double bilateral variable area optical soundtracks are recorded onto film and played back in cinemas.