Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Sound

ciechanow.ski

Post reply on HN
Print view View original

101–110 of 222 posts

Re: Sound

#101

Post by owenfi »

marcodiego wrote: post #100

WARNING: sounds you can't hear can still damages your ear. DO NOT INCREASE THE VOLUME ON INFRA OR ULTRA SOUNDS BECAUSE YOU CAN'T HEAR THEM

Would love some additional info on this if you are aware of any. My intuition says (and could very well be very wrong) sound at one frequency would only damage that or very nearby frequencies hearing range? If wrong I'm curious what the range of damage is (I'm interested in exploring ultrasound data protocols, so curious what frequency I have to go to to avoid damaging anyone's - and potentially animals as well - hearing).

I also assume if you are starting at a reasonable (laptop, small desktop speakers) at a low-to-medium level (say 50-60dB), increasing a bit won't cause immediate damage even if you can't hear the sound?

Re: Sound

#102

Post by anigbrowl »

comboy wrote: post #39
WhitneyLand wrote: post #33

Earlier quoted context omitted.

Wow. Such a profound insight could not get published for 15 years because others couldn’t grasp it. Including Lagrange! It’s an uncomfortable reminder of how essential reputation and credibility are in the machinery of science. ”The paper contained the controversial claim that any continuous periodic signal could be represented as the sum of properly chosen sinusoidal waves. Among the reviewers were two of history's…

> Lagrange had insisted that such an approach could not be used to represent signals with corners, i.e., discontinuous slopes, such as in square waves. Isn't that true though? You can only approximate it, right?

Corners in signals are like limits in calculus or irrational numbers in arithmetic. Once you accept them as an abstraction that you can't touch them directly all the anxiety dissipates.

Re: Sound

#105

Post by anigbrowl »

voidhorse wrote: post #72
nonrandomstring wrote: post #20

+1 for the recommendation for "The Scientist and Engineer's Guide to Digital Signal Processing" by Steven W. Smith. I spoke to Steven many years ago about his putting all of the book PDFs online for free and since then have recommended at least 5 university libraries to buy it because the students could get free copies of a great book that can be referenced in the library. FWIW the The Scientist and Engineer's Guide…

I'm actually reading through it right now after trying out a few other DSP resources. It is by far the clearest and most approachable, without sacrificing much depth at all. It's a great book.

It's the best. I learned DSP from that ~20 years ago and still use those mental models whenever I need to think through a problem. A good book like that is a friend for life.

Re: Sound

#106

Post by zeroonetwothree »

Erwin wrote: post #68

I was surprised by how much I was surprised by the very first fact -- that air molecules move around at extremely high speed of 450m/s, but just bump into each other cancelling this speed out, and this speed is based on pressure & temperature. And it's due to this speed, despite air's low density, the force air exerts is enormous -- equivalent to 10 tons per square meter. Somehow, the human sandwich does not explode…

Note that diving to a depth of only 10m will double the external pressure on your body yet humans can easily survive this.

Indeed the all time record is >300m which is something like 32x pressure.

So it’s not merely that there is equivalent pressure from inside.

Re: Sound

#107

Post by behnamoh »

sgraaf wrote: post #52

Bartosz' blog posts are in a league of their own. They way he is able to explain complex subjects by starting from first principles, gently adding more and more layers, with beautiful, custom-made figures and animations is truly, literally, awesome. I strongly recommend supporting the author via his Patreon if you enjoy his blog posts.

This is how school must be. I'd rather pay people like him to create interactive content than pay the school to teach my kids useless material in dry, rigid ways.

Re: Sound

#108

Post by tambourine_man »

incanus77 wrote: post #19
tambourine_man wrote: post #18

Earlier quoted context omitted.

Right you are, thanks :facepalm

I still don’t understand why this mutes functionality like this page’s, but not web video or audio players or the like in web pages.

Yeah, iOS sound is an enigma. If you lower the sound, does it change the ringtone? How about the alarm?

No one knows for sure, one of the true mysteries of the universe.

Re: Sound

#109

Post by behnamoh »

mixmastamyk wrote: post #95
apitman wrote: post #75

I was 20 minutes into this before I realized the interactive bits were automatically turning themselves off and on based on which one was visible in the viewport. That seems obvious, but the fact that it worked so intuitively and without bugs on my system says a great deal. This is what master UX design looks like.

It’s a few lines of standard JavaScript. Nice touch used by many sites, not difficult.

> not difficult.

And yet, not so common especially on popular websites with $$$ development costs.

Re: Sound

#110

Post by behnamoh »

PostOnce wrote: post #79

This man needs a genius grant, and this is about the 6th time I've thought this. Any one of these pages would be a feat, an achievement to be proud of, but as a collection, it forms one of the greatest educational resources of its type that I have known. These things can give you more intuition about a subject in 45 minutes than a textbook might be able to in 3 months, because it's interesting and not dry. I wish I h…

> This man needs a genius grant, and this is about the 6th time I've thought this.

He says this is his weekend hobby. I really wish he could work on these things full-time. The world needs more people like him.

Post reply on HN