1	Rise Above the Jet Noise AVX Adaptive Encoding Jeremy Hoenack,CAS, MPSE Sound Trax Studios jhoenack@avxsound.com
2	AVX Inflight Sound Overview 1 Subtle dialog is clear and easy to understand Underscore and background effects that are normally lost are crisp and clear Film sound-track masks jet noise instead of reverse No high sound levels, no ear pain, no need to constantly adjust volume, natural sounding More immersion in film – more positive flight experience No new equipment – compatible with all IFE systems
3	AVX Inflight Sound Overview 2 Psycho-acoustic adaptive encoding Parses, disassembles, restructures the dynamic range in real time – constantly adapts to program content Enables full optimization of dynamic range to needs of human hearing without severe limitations of existing technology
4	AVX Inflight Sound Overview 3 Adaptive Encoder vs. Compressor/Limiter DSP intensive vs. analog design Unlimited design possibilities vs. practical limitations AVX “reverse-compression” emulates how brain deals with high ambient noise like conversation on a jet
5	IFE sound system – The Titanic Destined to cruise over sea of noise – 75db SPL (From take-off to landing, like sitting next to a vacuum cleaner, a hair dryer, or standing in the shower.) Can not change course very quickly – prohibitive costs Needs to accommodate all kinds of people and stuff – variety of headphones, hardware, media
6	Film sound track – The Iceberg Only the peaks are noticed Most of it obscured by sea of noise “Big picture” missing – no context Tells how to perceive visual (picture) Controls emotional response eg. fear Conveying the emotional content is life or death matter to a film Low emotion = low immersion
7	How much is hidden? Top of iceberg is 90db 15db is revealed Sea of noise level 75db 35db obscured by sea of noise Over 2/3 of sound (dynamic range) is buried beneath sea of noise Bottom of iceberg is >40db
8	Human hearing 1 Normal range 35-72db for speech (intelligibility) Below 75db sea of noise in cabin = 0% intelligibility Good news - No need to have foreign language tracks
9	Human hearing 2 Lose intelligibility if average speech less than 15 db above noise – 75 + 15 = 90db Narrow range for speech 15 db – average at 90db (unsafe), peaks at 97db Bad news - Above 85db – no increase in intelligibility – instead oppression and discomfort
10	How to uncover the iceberg? Can not change noise level - 75db Iceberg is 50db high (dynamic range) 90db-40db Can not lift above noise level 5db+75db=125db !!!!! 90db beginning of “unsafe levels” (D.O.L.), discomfort 2 hours @ 100db = hearing damage – long flights?
11	Existing technology ineffective 1 Squeezes to 30-40db range Ear discomfort from peaks Obscured mood fx / underscore Straining to understand – low intelligibility Jet noise “in front” of sound track Like looking through dirty glass Constant volume adjustments Little or no immersion in film
12	Existing technology ineffective 2 Operates from top down Characteristics of electronics Compressor Limiter Unnatural Real life is opposite Limited by artifact -claustrophobic
13	Human hearing psychology 1 Decoding, decoding, decoding Sound into phonemes Phonemes into words Words into language Language into meaning Brain overwhelmed Sound buried in noise Playing “catch-up” -Trying to figure out what was missed while trying to continue in-the-moment decoding
14	Human hearing psychology 2 Failure & frustration No one likes to feel stupid Not knowing “what’s going on” Missing vital information that “others know” Ability to make emotional associations is blocked by obsession to decode
15	Brainy brain has no problem Why we can have a normal conversation above the noise? Brain uses “reverse-compression” to raise bottom with little affect on top High intelligibility with acceptable levels Normal speech pattern -subconsciously adapt to ambient noise
16	AVX one-ups the brain 1 Extreme reverse-compress/limit micro-encodes detail Top is normal – ‘must be normal’ Comfortable levels Dynamic range fits
17	AVX one-ups the brain 2 Raises bottom of sound track above noise Mask effect – sound track is relentlessly dominant Mind tunes out and soon forgets subordinate jet noise (it wants to)
18	AVX one-ups the brain 3 Enhanced aural cues ~100% intelligibility including spatial cues Sound decoding easy & relaxing Brain resources free to make deep emotional associations High level of immersion in film Tune out flying – trip is shorter and more enjoyable
19	Film Clips from SECONDHAND LIONS comparing WAEA 1289-1 spec. audio with AVX encoded audio Clips mixed with jet noise @~73db for simulation All clips are at the same volume level Louder sounds are similar AVX raises quiet sounds
20	Per 1289-1 spec. #1 Inaudible under bridge, cop, plane approach
21	AVX Encoded #1 Distinct snoring & ambience under bridge, plane approach
22	Per 1289-1 spec. #2 Inaudible off camera speech, music and ambience
23	AVX Encoded #2 Speech is intelligible, distinct music and ambience
24	Per 1289-1 spec. #3 Inaudible lion growls, weak ambience, lack of presence
25	AVX Encoded #3 Distinct lion growls, ambience is dominant, speech has good presence
26	Per 1289-1 spec. #4 Inaudible bell-tree, no presence to music and ambience
27	AVX Encoded #4 Distinct bell-tree, good presence of music and ambience
28	Per 1289-1 spec. #5 Inaudible ambience, unclear speech at end
29	AVX Encoded #5 Better ambience, distinct speech at end “learn to do without” & “uh-huh”
30	Per 1289-1 spec. #6 Speech is frustrating - unclear, music missing until end
31	AVX Encoded #6 Speech is intelligible, music is marginally audible
32	Per 1289-1 spec. #7 Speech is marginal, jet noise dominates
33	AVX Encoded #7 Speech is crisp and present, music and ambience dominate over jet noise
34	Per 1289-1 spec. #8 Jet noise dominates, missing/obscure lion sound, ambience very weak
35	AVX Encoded #8 Sound track dominates, lion & ambience clear, presence, “in the movie”
36	Per 1289-1 spec. #9 Jet noise dominates, speech lacks presence, ambience very weak
37	AVX Encoded #9 Track dominates, speech is intimate & clear, ambience, reverb, presence, “in the movie”
38	Summary AVX solves the difficult noise problem for IFE films Film perceived as intended High immersion > enjoyment > successful distraction Greater satisfaction & positive impression of flight
39	AVX 757 Simulator Demo 5-8 after show, 10 minute drive west near Disney & Warner Bros. Sound Trax Studios 2815 West Burbank Blvd. Burbank 818-842-6300
40	AVX would like to thank WAEA attendees John Salzman John Eargle & Chris Foreman –sound reinforcement research Avid Airline Products – headphones Sound Trax Studios New Line Cinema