Director Christopher Nolan's Interstellar is already a hit at the box office, taking in over $326 million worldwide after just one week in release. Despite the overwhelmingly positive reactions from fans and critics alike, the film has been taking some heat for its approach to the sound, with several fans complaining that many key lines of dialogue are difficult to hear. Questions have been raised about whether it's the director's fault, or the theaters, but the filmmaker revealed in an interview with The Hollywood Reporter that the sound is exactly how he wanted it.

"I've always loved films that approach sound in an impressionistic way and that is an unusual approach for a mainstream blockbuster, but I feel it's the right approach for this experiential film. Many of the filmmakers I've admired over the years have used sound in bold and adventurous ways. I don't agree with the idea that you can only achieve clarity through dialogue. Clarity of story, clarity of emotions - I try to achieve that in a very layered way using all the different things at my disposal - picture and sound."

He went on to praise theaters for presenting the sound in this unconventional way, exactly how he envisioned it, after visiting theaters such as TCL Chinese Imax Theatre and the Arclight Cinerama Dome in Hollywood and the AMC Loews Lincoln Square in New York.

"Usually [I visit] six or seven. I like to hear it out where people are going to see it, not just in the cocoon of the dub stage. That is something I have done for years, because everything we are doing is intended to communicate something to the audience. The theaters I have been at have been doing a terrific job in terms of presenting the film in the way I intended. Broadly speaking, there is no question when you mix a film in an unconventional way as this, you're bound to catch some people off guard, but hopefully people can appreciate the experience for what it's intended to be."

The filmmaker also discussed working with Hans Zimmer, re-recording mixers Gary Rizzo and Gregg Landaker and sound designer Richard King.

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"We made carefully considered creative decisions. There are particular moments in this film where I decided to use dialogue as a sound effect, so sometimes it's mixed slightly underneath the other sound effects or in the other sound effects to emphasize how loud the surrounding noise is. It's not that nobody has ever done these things before, but it's a little unconventional for a Hollywood movie."

One example the filmmaker gave was a scene where Matthew McConaughey's Cooper is driving through a cornfield, where the director actually rode in the back of the car.

"It's incredibly loud ... exhilarating and slightly frightening," he laughed as he described his experience. "I was very keen to try and give the audience the experience and the chaotic feeling with the sound. The idea is to experience the journey the character is going on. [For instance] the experience of being in the cockpit is you hear the creaking [of the spacecraft]; it's a very scary sound. We wanted to be true to the experience of space travel. We wanted to emphasize those intimate elements. I also love the quality of the sounds Richard got inside the truck. It's echoed later in the film, with one of the key spaceship scenes. To me, there's something very frightening about feeling the environment affecting the vehicle or the capsule you are in - whether it's sand and dust hitting the windows of the truck you are in or the atmospherical forces while you are traveling in a space capsule."

He also discussed one of his favorite scenes, where several characters are driving through a dust storm.

"I love sound cuts that play with point of view (in this case, the sound of the dust hitting the car, as heard from both outside and inside the truck). When the camera cuts outside the car, the sound cuts with it. You have that feeling of the elements barraging you - and you're out there in it."

He also talked about using different sounds and themes for the different planets visited in Interstellar.

"We wanted to avoid the traditional layering of sound. We wanted to distinguish the worlds based on very intimate, recognizable sounds. The water planet was a lot of splashing. In contrast the ice planet had the crunch of the glaciers."

He also discussed a scene where Michael Caine's character speaks with Jessica Chastain's character from a hospital bed.

"The creative intent there is to be truthful to the situation - an elderly man dying and saying something somewhat unexpected. We are following the emotional state of Jessica's character as she starts to understand what he's been saying. Information is communicated in various different ways over the next few scenes. That's the way I like to work; I don't like to hang everything on one particular line. I like to follow the experience of the character."

The filmmaker also spoke about the months they spend on the sound mix.

"We mixed for months and months and we talked about everything. We must have mixed this film over six months. It was a continuous, organic process and discussion."

What do you think about Christopher Nolan's approach to sound in Interstellar? Chime in with your thoughts below.