Hacker Newsnew | past | comments | ask | show | jobs | submitlogin

Probably the most brilliant contributor to the art of sound design is a guy called Walter Murch. He's somewhat of a polymath in film, as he not only designed the sound for The Godather trilogy and Apocalypse Now, but he also edited the picture.

Anyway, Murch put a lot of his thoughts about both editing and sound into a book called 'In the Blink of an Eye', which is still read by film students today. One passage that always stuck with me is an informal rule that Murch gave himself after he discovered something odd about the interplay between sound and audience immersion. After a lot of experimentaiton, Murch found that in any 'moment' of a film (say 3 - 7 seconds), an audience can only process 2-3 layers of sound playing at once.

For example, Michael Corleone goes to meet Moe Greene and they're walking through the lobby. We hear footsteps, the elevator ding, and the atmos of the hotel. If Murch had added the sound of he luggage of the bell-boys or some guests arguing in the rooms, it would be too overwhelming for us and the verisimilitude of the film would become compromised.

I guess I'm mentioning Murch because this informal sound rule was always independent of speech from the actors, which he doesn't treat as a layer of sound. To me, this may be a very practical example of what these researchers seem to be finding: that there is indeed some parallel processing going on with speech and sound in our auditory cortex.



I'm often curious about the audio approach used in a bunch of 1960s films where multiple people are talking over each other. It's very deliberate, but I don't know the terminology. The Graduate is an example, I think in the party scenes near the beginning. In that example, it seems intended to convey the feeling of being overwhelmed. But there are films and TV where it's less about being overwhelmed and more about an immersive experience, to conjour a bustling environment like being at a busy family meal. I think M * A * S * H did it occasionally in the surgery scenes.

I always find it very noticeable when it I see it. There's something jarring about it, the experience is somehow very different from a real multiparty conversation, possibly because it's impossible (for me) to focus my attention on any one speaker. That may be deliberate, of course, although often these scenes include key information in the overlapping dialogues.

It's a technique I never see in modern film/TV.


Consider visually processing (counting at a glance):

X X X X

and

X X X X X

How many are in the first? How many in the second?

It's my rule of thumb that all human pre-attentive processing can handle 4s at the pre-attentive level, and 5s+ require cognitive engagement.

This sound rule here seems to be the same: voice + 3.


The "counting low numbers of things instantly" thing has a name: Subitizing. It's quite the fascinating topic.

https://en.wikipedia.org/wiki/Subitizing

Also, it's apparently not restricted to counting:

> A 2006 study demonstrated that subitizing and counting are not restricted to visual perception, but also extend to tactile perception, when observers had to name the number of stimulated fingertips.[7] A 2008 study also demonstrated subitizing and counting in auditory perception.[8] Even though the existence of subitizing in tactile perception has been questioned,[9] this effect has been replicated many times and can be therefore considered as robust.[10][11][12] The subitizing effect has also been obtained in tactile perception with congenitally blind adults.[13] Together, these findings support the idea that subitizing is a general perceptual mechanism extending to auditory and tactile processing.


I learned in a documentary that pople who play some video games can immediately recognize 5-7. They tested with a handful of grapes.

I can reliably recognize up to 6 in most cases.


That is really interesting. I added a comment below: https://news.ycombinator.com/item?id=28988027

I wonder if that has something to do with it




Consider applying for YC's Winter 2026 batch! Applications are open till Nov 10

Guidelines | FAQ | Lists | API | Security | Legal | Apply to YC | Contact

Search: