Tuesday, January 08, 2008


Today I was looking for the McGurk effect video I found a while ago, to send to a friend. I was trying to convince her that sound is is something that our brains construct, not something that is 'out there.' (Vibrating waves are 'out there,' but sound isn't. The waves hit our ears and we construct the sound inside our heads.)

She was not convinced. She wanted to believe that sound must be something objective.

I found the McGurk effect video I was looking for (listen while watching, then listen with your eyes shut. What is different?), plus a few others demonstrating the same thing, and in doing so I also came across this page, which I am finding nicely complements the book I am reading about music.

But I also discovered that my ears are younger than I am. I eventually found myself on the page where you can listen to pink noise (you didn't know there was such a thing as pink noise, did you? Neither did I), and clicked on the various frequencies. Then I got to the one that said,

"Pink noise 16,000 (if you are in your 30s, you might have problems hearing this. If you are older, you might even have problems with 10kHz or 12.5 KhZ)."

Apparently my ears are not yet in their 30s, even if the rest of me is racing towards decrepitude. Also, I am sure there is some species of cicada that makes noises at 16,000 Hz here in Japan, because the first thing that popped into my head when I heard that was, Somebody kill that bug before it drives me up the wall!

It is a REALLY ANNOYING sound.

I cannot hear the 20,000 Hz one, though. You could probably upset your dog with that.

(Perhaps I could when I was younger. When I was a high school student, I remember our science teacher playing sounds on a machine while we all stood up, and we had to sit down when we couldn't hear them any more. After a while I was the only one standing, and the teacher scoffed and told me only dogs could hear that, don't be silly. Then he turned the sound off and on and off and on and had me popping up and down from my chair until I started feeling dizzy. That was a bit irritating. Especially when he turned it on again, later in the lesson, and I popped out of my chair like a well-trained dog and yelled at him to STOP DOING THAT, PLEASE? IT HURTS MY EARS! I don't think I'd ever yelled at a teacher before. I was usually a well-behaved child.)

Anyway, all of this means that tonight I did not get the work done I was supposed to get done, and I will have to do it tomorrow evening instead, after work.

Incidentally, I finished work at my Tuesday university today, including getting the grades done and handed in. All the students had a chance to challenge the grade I was giving them, and only one did. (It was my mistake – I'd missed adding in one of his homework assignments, and I'm glad he spotted it.) I am feeling terrifically efficient.

At least I WAS feeling terrifically efficient, until I got distracted by the interestingness of sound.


Lia said...

What is pink about pink noise?

Cheryl said...

Wonderful fun - thanks for the link.
Its fascinating - and so is Lia's question!

Carrie said...

That first video is crazy! I didn't believe it was going to be anything sensational so I was really surprised when I closed my eyes and it was a totally different sound.

I've heard of pink noise before and at the time I could hear it. I have always had sensitive hearing, much to the dismay of my former students.

Badaunt said...

There's an explanation of pink sound here, but I don't REALLY get it. From what I gather, white sound is all the sounds across the spectrum equally, but with pink sound the higher frequencies are played at a lower sound level. (I think 'lower sound level' refers to what we'd call the volume.)

Carrie, I agree about the McGurk effect thing. It's crazy. I came across it a few years ago, and a couple of times since then I've hunted it out again because it's too weird, and I need to hear it again to believe what happens.

Faerunner said...

Interestingly enough, I heard the intended (spoken) sound in the video instead of the combined or visually-linked sound, the first time with my eyes open. I've never been any good at lip reading though, which explains my results very well. (this leads to problems in very loud settings or in classrooms when people try to lip-speak to me and I have to smile and nod and not catch a word of it).

Also, my laptop speakers are apparently about as horrible as one can get (I assumed this before I tried the noise files) and so ones I should have been able to hear sometimes didn't play at all. I shall have to remember to try this with the boy's 5.1 surround sound speakers instead. Sound is so fascinating!