After my morning run (a beautiful but hard 11 miles along the Southern California coast), I came to the studio to set up the room for a film mix that’s going to happen on Monday and Tuesday. Andy Hay, the go to guy in the world of independent film mixing and overall ace audio guy and I spent a couple of hours routing this and that, checking out the new near field monitors and making sure there was a hot microphone in the room for some lines that may have to be re-recorded.<\/p>\n
And we got talking about film sound, monitor systems, the X Curve, DCP and…my favorite topic…high-resolution sound. I asked him if any films were being done in high-res audio. The answer is no, not that he’s aware of. <\/p>\n
If you think going to the movies or listening to your favorite cinematic feature in your home theater delivers a great audio experience, you’re sadly mistaken. I thought that only music lovers are had fidelity problems…we’re getting great sound compared to film sound!<\/p>\n
My mixing room is equipped with a THX certified set of JBL speakers…you know, the big ones with the horn drivers and a woofer for the low end. There is also a large subwoofer for the LFE (Low Frequency Enhancement) channel, my trusty TML Labs “Profunder” driven by 500 watts of Bryston power. Andy mixes “in the box”, which means that a surface controller makes changes to the Pro Tools sequences and plug ins. Mixers don’t want to mix dialog, music and effects with a mouse. Control surfaces use a simple Ethernet connection to allow the virtual faders on the computer monitor to be moved by the physical faders on the surface.<\/p>\n
All audio for films is PCM at 48 kHz\/24-bits. The actors are recorded by the production sound mixer at 48 kHz\/24-bits, the foley and ADR (automatic dialog replacement) are recorded at 48 kHz\/24-bits and the mix is output as part of a DCP (Digital Cinema Package) for final delivery with the visuals…at 48 kHz\/24-bits PCM. Nothing high-resolution about any stage of the production. And it gets worse.<\/p>\n
For “consistency”, there is an aggressive low pass filter applied to the full range audio before you get to hear the soundtrack. It’s called the “X-Curve”. Sounds pretty exotic, doesn’t it? How bad could a little high frequency rolloff be? After all, it’s only dialog, a little underscore and a few sound effects, right? It’s hugely bad…and I had no idea until today.<\/p>\n
The X-Curve is based on the Film Academy curve. See the illustration below (which was borrowed and recreated from an interview with audio pioneer Loan Allen, on the editors guild website<\/a>).<\/p>\n
![\"140418_x_curve\"](\"http:\/\/www.realhd-audio.com\/wp-content\/uploads\/2014\/04\/140418_x_curve.jpg\")
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