What Brain Can Explain In Layman's Terms.....

How do lasers play music on CDs & play images on DVDs?

I mean I still don't understand how music can come from melted vinyl formed into an album (LP) with grooves & we know how many years behind the times I am on that!

If you know the answer to it as well, feel free, I'm all ears

Re: What Brain Can Explain In Layman's Terms.....

In the words of Homer Simpson.

"Lord help me, I'm just not that bright."

"Every time I learn something new it pushes some old stuff out of my brain."

Hope someone can answer your query,

Re: What Brain Can Explain In Layman's Terms.....

Ha! I really, really like that line! It's my new excuse.
For everything!
Ta muchly!

Re: What Brain Can Explain In Layman's Terms.....

Tis all about blips and blobs innit, crevices annat - oh and distances.

So there you go - sorted.

Re: What Brain Can Explain In Layman's Terms.....

Sound is a vibration hundred of times a second in air. In old fashioned recording the sound vibrations were recorded directly as vibrations or wiggles in a groove or track cut directly into the master record. The recording was then reproduced by being impressed into vinyl records. A stylus in a record player picked up the vibrations when placed in the groove as the record rotated beneath it. The sound picked up by the stylus was amplified directly.

In CDs the music is recorded digitally by being converted to a series of ones and zeros. These are recorded as a series of bumps in a spiral track on the CD. Loosely speaking the laser is the equivalent of the stylus in a record player. It reads the bumps on the CD and a digital-to-analogue converter converts the numbers back into electronic vibrations, which are amplified, and then sent to your sound system's speakers.

Re: What Brain Can Explain In Layman's Terms.....

Thanks Griffon but 'how' does a laser read the series of bumps?
Also, with record albums how was the sound vibrations actually captured, with a fishnet?

Re: What Brain Can Explain In Layman's Terms.....

Want me to have a stab at this again?

Re: What Brain Can Explain In Layman's Terms.....

Are you a brain?

Not unless you have every single detail down explanatory in everyday terms mister!!!!

Re: What Brain Can Explain In Layman's Terms.....

Ok then, all in layman's lang.

Say your cd got a tiny lump on it well the laser shines down on the lump and reflects off it back to a receiver. The time it takes - or distance measured - equates to a note etc. So it could stand for an f sharp for instance.

See simples ...

Or you could just wait for Griffon's reply if the above is just too complex for you .

Re: What Brain Can Explain In Layman's Terms.....

You remember and understand the gooves in a record and know that they are the shape of the wave form that makes the sound.

If you imagine that you measure the height of that wave form at regular intervals then record the number in binary so the number can be recorded as a series of.1 and 0s or pits and flats or ons and offs or 5volts and 0volt then you can reproduce the original sound. The only information you need apart from the binary numbers is how often they were originally recorded. Eg 19200 times a second - similar to playing a record at 45rpm or 33rpm to make it sound right.

Decimal to Binary counting. Bytes are 8 bits thus

128 64 32 16 8 4 2 1

So 32 would be 00100000

3 would be 2+1 so 00000011

And 255 would be 11111111

Simple really