?

Log in

No account? Create an account

Interesting notes - Journal of Omnifarious

Jun. 6th, 2004

10:08 pm - Interesting notes

Previous Entry Share Next Entry

An interesting bunch of information about how various famous and prolific geeks organize their lives. I may have to take a few tips from this. Maybe use my blog here more for thoughts on projects and things.

Here's a link to it on my own server in case it disappears from the other one.


On that note, I had an interesting idea today. Noise cancelling microphones are neat, but one difficulty is deciding exactly what's noise, and what's something you want to keep. I'm not sure how current noise cancelling microphones do this, but I thought of a way to do it. This may even be how humans manage to listen to just one person talking in a noisy environment filled with people talking...

You have two or three microphones, and you make some decision about some component of your signal that isn't noise. Then you measure the timing differences between that signal showing up at the different microphones. That gives you a spatial location. So you can look for other signals who's timing indicates that they come from a spatial location very nearby the one the signal you know you're interest in comes from. You can tell this by similar timing patterns. With good, sensitive electronics for detecting the timing differences, the different microphones don't have to be that far away from eachother.

Current Mood: [mood icon] thoughtful
Current Music: Out of My Mind - Duran Duran

Comments:

[User Picture]
From:zaiah
Date:June 6th, 2004 11:37 pm (UTC)
(Link)
This would have been one of the questions off of LAST term's Physics final.. good thing I don't have to remember any of THAT> :P pbbttlllsss.
(Reply) (Thread)
[User Picture]
From:omnifarious
Date:June 7th, 2004 09:18 am (UTC)
(Link)

*laugh*

(Reply) (Parent) (Thread)
[User Picture]
From:kestrell
Date:June 7th, 2004 06:40 am (UTC)
(Link)
Interesting thoughts about noise cancellation: this is the number one most difficult but most important skill I had to learn as a blind person. Public streets with lots of traffic, atriums with hundreds or thousands of people, it's difficult in these environments to distinguish important sounds from noise. I had to learn to focus on what was close and try to ignore things not near my personal bubble, but it is hard to learn to ignore people screaming at each other. Also, sound, unlike sight, only has a kind of distance to it sometimes, most of the time all sounds seem equidistant, unless you are an owl. Have you noticed how modern buildings especially those built in the past decade and going up right now are built with no walls, no acoustic considerations, nothing to prevent all sound within it from seeming equidistant? I walk into these buildings, think of a mall or a new campus center, and all I get is a thousand small noises producing one big static signal.
(Reply) (Thread)
[User Picture]
From:omnifarious
Date:June 7th, 2004 07:14 am (UTC)
(Link)

That's interesting to learn.

I know we spatially locate sound sources by measuring delay. That also tells me why we can't spatially locate low-frequency sounds. The wavelength of such sounds is larger than the space between our ears.

I wonder what it is about those spaces that make it hard to spatially locate sound. Is it because there are there lots of echoes off the walls?

(Reply) (Parent) (Thread)