thinking about records. (or the fact that we can record sound at all)

Does anyone else find it completely astonishing that we arecapable of building machines that can recieve sound waves, and then record them to be played back at a later time? I look at a vinyl album and I cannot imagine that anyone was able to invent such a thing. How can those little grooves recreate sound? How can a machine be smart enough to turn sound waves into a tangible object?

I was just tripping out on that for a while last night.

i get like that too......yous hould check out a replay of the engineering of Rome on the history channel...that stuff blows my mind too

yeah, I never think I want to watch stuff like that. but if I'm flipping through channels and happen to pause on it for a few minutes, I'm hooked. Funny how I usually prefer to watch mindless TV instead of the educational stuff. My ex was all about the history channel and I didn't love watching it, but I actually learned a lot (History was one of my most subjects in school. I'm totally a math girl)

the aquaducts, and the buildings of Rome are mind boggling it really shows how litltle we have progressed in 2000 years.....another thing that gets me, not because of recent situations, but how much gasoline we consume....driving and seeing all of these cars that use as much gas as me and thats just in Toledo Ohio, how much gas is actually being used in cars, trying to picture that visually in an open space.....i just about implode.

This has actually been on my mind a lot lately, as well. I mean.. how is sound translated into a disc, or a tape, or a piece of vinyl, and then back again? And a tiny little laser is able to interpret all of that? Amazing

the computer disc part doesn't baffle me as much, simply because i think of computers as so magical in and of themselves, that their ability to do things doesn't really surprise me anymore, but tapes recording auidio...or video AND audio...even more astonishing. How does a machine see? And the phonograph was invented when? well over 100 years ago. there are a lot of dumb people in the world these days, but some people are fucking brilliant.

Things like this really make me want to studio audio.

I was thinking the same thing this week while watching a record spin. It just baffles me that a little needle can follow the grooves on a spinning disc and turn it into sonic magic.

Sound waves are made by modulating air pressures that are picked up by the ear drum and converted to electrical energy and interpreted by the brain.

The diaphragm of a microphone acts in the same way as the ear drum and the sound is converted to electrical energy (voltage) in which the on/off of the voltage represents the compressions and rarefactions (more dense/less dense air) of the acoustic energy.

Digital music is a representation of this information using 1s and 0s instead of voltages. When sound is played back it's just converted in the opposite direction and the speaker vibrates at high speeds to create the acoustic energy much like our vocal cords do.

But yeah.. it's all pretty cool

like I said, the computerized technology doesn't surprise me much. how do the grooves work on a record though?

sound doesn't move up and down like a sine wave (it's alternating higher and lower air densities), but it can be represented that way. the grooves on vinyl cause the needle to mimic the wave pattern of the sound. when it's played back, the motion of the needle is converted to electrical energy, which is then converted to acoustic energy by the speaker.

Here's how a sound wave is represented by a sine wave:



and here's a closeup of a vinyl record:



What's really cool is that stero recordings use vertical motion as well as horizontal motion to carry the signals from both channels.