What's so bad about Night Listening Mode? (Dynamic Range Compression)

What's So Bad About Night Listening Mode?

Starry Night

brought to you by

Alpha Certification

www.tmlaboratories.com

Night mode, or Dynamic Range Compression (DRC), is designed for less-than-optimal listening situations. These include listening at lower level at night so you don't annoy the neighbors, or if you are just casually watching a movie and don't want the full effect of the sound. It's also the standard mode for low-priced consumer items which cannot reproduce the full range of a movie soundtrack.

But some home theater owners ALWAYS use this mode. We think that this is a big mistake.

DRC for movies is designed to compress the original 105 dB (decibels) of soundtrack dynamic range to around 75 or 78 dB, depending on the exact DRC profile specified on the DVD. That's a loss of up to 30 dB of dynamic range! For comparison, the difference between AM and FM radio is only 20 dB of dynamic range.

But we believe that you should hear all of the sound. You paid for it in the quality of the home theater equipment you purchased. Why reduce your sound quality to significantly less than you get in a commercial movie theater, or from much lower priced equipment?

The solution is the same one used in all modern commercial movie theaters: proper acoustical treatment. This is an integral part of your home theater, just like the speakers and DVD player.

Until recently, acoustical testing and diagnosis was very expensive. Since professional testing wasn't done at the home theater level, acoustical treatment was a hit-or-miss process. The best an installer could do was a simple real-time frequency analysis to see how "flat" your room was. This type of testing measures only stationary signals in the frequency domain. It can't do dynamic time-domain measurements, which are necessary to isolate and correct the causes of poor dialog intelligibility.

Alpha Certification^SM has forever changed that. We do the same testing and custom analysis that an on-site acoustician does (if you can afford one!). Alpha Certification means that a home theater is as acoustically precise as the best commercial movie theaters.