Quiz on the CD concept

[disco1999]

Here's an unusual one for you guys, if you were to read the contents of a CD on a straight line instead of spiral, how long would the track measure ?

2nd question: What year was the first 33 rpm vinyl LP played ?

[Bernie]

On 2002-08-27 08:45, disco1999 wrote:
Here's an unusual one for you guys, if you were to read the contents of a CD on a straight line instead of spiral, how long would the track measure ?

2nd question: What year was the first 33 rpm vinyl LP played ?

I'll pass on the first, but as far as I can recall, the 33 1/3 LP was introduced by Columbia in the 1940s.

[disco1999]

Close Bernie. The long-playing or LP record 12" in diameter known as a monaural phonograph record first introduced in the year 1948. It was designed to be played at a speed of 33 1/3 rpm with microgroove that is a spiral 90 degree v-shaped or at right angles which is impressed into the vinyl plastic permitting a playing time of between 25 to 30 minutes per side.

Now does anyone dare to take a guess for the CD ??

[pong38]

On 2002-08-27 08:45, disco1999 wrote:
Here's an unusual one for you guys, if you were to read the contents of a CD on a straight line instead of spiral, how long would the track measure ?

ehhh..

3,5 miles ?

[Blaxman]

Hmmmm.......16 Kilometers!?!?! No!?! Hmmmm.....back to Discovery Channel!! :lol:

[disco1999]

How about 1.642 light years ?
Just kidding, it is estimated to be over 500 meters.

Now, who can tell what is the average life span of an unused compact disc in normal storage conditions.

[Bernie]

On 2002-08-28 07:58, disco1999 wrote:
How about 1.642 light years ?
Just kidding, it is estimated to be over 500 meters.

Now, who can tell what is the average life span of an unused compact disc in normal storage conditions.

When I used to sell audio & video equipment the manufacturer reps used to quote crazy things like 100 years, but we'll never truly know till then.

[QUINNY]

How long is a CD?
let's say one of 74 minutes.
CD spins at an average 900 RPM?
74 X 900 = 66,600 total revolutions
average circumfrence= 7"
66,600 X 7" = 466,200", = 38,850 feet
38,850 feet = 12950 yards = 7.36 miles
So I reckon 500 metres is way off.

Even if a CD spins at ave 300 RPM
the answer would be 2.45 miles.

I'm sure the answer lies somewhere.

[QUINNY]

I've just found the answer;
CD is 11.7 Kilometres
a DVD is 111. something Km.
Whoopee!!!

[pong38]

Guys,

I tought I gave you the right answer already but nobody have read it.

The answer I gave you is c/p by me and can be found here : http://www.howstuffworks.com/cd1.htm

"The incredibly small dimensions of the bumps make the spiral track on a CD extremely long. If you could lift the data track off a CD and stretch it out into a straight line, it would be 0.5 microns wide and almost 3.5 miles (5 km) long!"

*snif*

Ron

[BrunoRepublic]

Well, unlike vinyl, CDs don't spin at a constant rate. The speed is about 600 rpm at the start (center) of the disc, and slows down to about 200 rpm at the end of a 70+ minute disc.

Furthermore, does one use an 80-minute disc as a benchmark, even though these exceed the original red book specifications of 74 minutes?

[QUINNY]

GrahamStart: So if it spins at 200 - 600 rpm the average is 400rpm (I know that's not entirely scientific, but it's good enough).
Average circuference of any track approx 7 inches
74 minute disc = 74X 400 =29600 total revolutions X 7" =207200 inches = 17267 feet = 5755 yards = 3.27 miles.
BUT as I said, the answer is actually 11.7 KM or 7.3 miles.

[disco1999]

Not sure who got the truth about this issue but I got my sources on http://www.vinylrecordscollector.co.uk
The author pretends a CD will last 15-20 years before corrosion starts eating the inner layers of the CD, therefore killing the media. Make copies guys. :-/

[Nano]

About when the CD started, 1983 is the year usually quoted for its invention. However, I read that the first music CD released was Dire Straits' "Brothers in arms", which is from 1985.
About the LP: I'm still looking for the exact first album released and year (I always wanted to know that), but I think it wasn't in the Forties. Jazz musicians, who were still the rage in the Forties, kept recording singles (at that time called just "records", 'coz the concept of an "album" didn't exist yet). Charlie Parker, for example, died in 1955 without ever recording an entire LP; "Birth of the cool", the "first" Miles Davis LP, is actually a compilation of all the single records he had done on the "cool" style by 1949/50 (the album was released in 1956). But by mid-decade Prestige was releasing entire albums of Miles' recording sessions, and when he signed to Columbia in 1955, he started to record with the LP format in mind. Riverside, another influent jazz indie of that time, released their first LP also in 1955 (it was "Plays Duke Ellington" by Thelonious Monk).
Rhythm & Blues was similarly restricted to a "single" form until the birth of rock 'n roll. The first R n'R LP released that I know of is Elvis first album for RCA in 1956 (the one with his name in big pink and green letters). So my guess is the very first LP appeared somewhere between 1952/55.

[BrunoRepublic]

On 2002-08-30 12:31, Nano wrote:
About when the CD started, 1983 is the year usually quoted for its invention. However, I read that the first music CD released was Dire Straits' "Brothers in arms", which is from 1985.

I think Brothers In Arms might have been the first CD to go gold or platinum, but it was definitely *not* the first CD released. I have several albums that were released on CD earlier than that.

I'm pretty sure that the first CD would've been a classical title... possibly Beethoven's 9th, as this piece of music is supposedly what determined the 74-minute length of the format. The first pop CD was Jean-Michel Jarre's "Oxygene".

What I find almost hilarous is that the CD was not originally intended to be a mass-market format. At the time, it was thought that only serious audiophiles would go for it, and the masses would stay with vinyl. Now it's almost 20 years later, and the exact opposite has occurred. :lol:

[Bernie]

BTW, the CD was officially introduced in 1982 in Europe & Japan and in '83 in the US. I still recall the big what-to-do on the CD's 10th anniversary.

Graham, you're right about the first CD release being a classical one, but I don't recall which one. In the US, The first pop release was Billy Joel's "52nd Street."

[pong38]

On 2002-08-31 09:42, Bernie wrote:
BTW, the CD was officially introduced in 1982 in Europe...

And (no joke), at the HQ of Philips in Holland I am still listed as the first person ever who proved the cd CAN be damaged so it is unplayable

Back in March '82 I was a salesperson for audio equipment (a very young one) and Philips made a test-cd (very first cd in public - track "Blue eyes" from Elton John) + a cd player to show the public what the cd was and how it sounded.
Me, the fool, not only demonstrated the audio quality but also scratched the cd (with a little help from the corner of a table) to prove it was "fool"-prove...
NOT... the cd couldn't be reckognized by the player anymore.
I got blacklisted by Philips and almost fired from my job. (the cd cost only a few thousand dollars at that time)

Those were the days...

Ron

[QUINNY]

So you were the guy who HAD To........
The misconception is even more acute today with CD-Rs, which are really very poor once even small scratches get on them.
MINIDISC rules (for consumer digital playback and recording) so far as I'm concerned.

[pong38]

What could I do...

I was young and innocent and I wanted to show the world (two customers) how great the compact disc (we didn't call IT "cd" that time) was.

It was Philips who told us the compact disc could play under all circumstances.

Wrong

[disco1999]

Besides scratches, did any of you guys have any problems with a degraded commercial CD (corrosion related) ??

[BrunoRepublic]

In over 15 years of buying CDs, I've only come across two such problems:

1: Garry Hughes "Sacred Cities". The disc has so many pinholes that it's almost transparent. It still plays, but not very well -- imaging problems, CD player has trouble finding tracks, etc.

2: PDO UK CDs from the late 80s/early 90s: These have a serious flaw that is now well-documented -- the discs are very prone to corrosion. You will see dark splotches on the edge of the disc that gradually grow and destroy the disc. If you have any of these, back them up NOW. The discs are quite distinctive in appearance, having a much smaller transparent center area than most CDs, as well as rounded edges (that make the disc slip out of your hands very easily!)

OTOH, I have a Robert Schroeder CD that was pressed by PDO Germany in 1984, and it still plays fine.

Regarding problems with CD-Rs... bear in mind that the CD was never intended to be a recordable format, so the fact that it works at all is pretty amazing. For best results:

1) Use good quality blanks for audio, and save the cheap ones for Data CD-Rs. Audio CDs do not have good error-correction, unlike Data CDRs (this is why you can't fit as much data on a disc as you can audio). Exactly which are best depends on your CD burner, but see if the burner's manufacturer has any specific recommendations. I've had good success with Verbatim Data Life Plus, Kodak (sadly no longer manufacturing CDRs), Maxell, and Mitsui. Supposedly Mitsui are the best overall, but they can be hard to find in some places (I have to go to specialty shops for them).

2) Do not use 700MB (80 minute) blanks. Stick to 640/74. This is the original spec for the CD. Many older CD players, and even a lot of the newer cheap boom-box style ones, will have problems with 80-minute discs, even if less than 74 minutes has been recorded.

3) Burn disc-at-once. Again, this is the original spec for the CD.

4) Don't burn at maximum speed. Having said that, the old advice "stick to 1x or 2x speed" is no longer true. Some brands will actually give better results burning at higher speeds. There is now a type of Maxell CDR that is designed specifically for high-speed, and won't work at 1x.

[Nano]

Mmmm... seems Bernie's right after all. Found in a trivia book (of course, looking for an entirely different bit of info) tnat the 33 1/3 LP was introduced by the Columbia Broadcasting System (CBS) in 1948. The engineer responsible for that landmark was called Peter Goldmark (no pun intended). Sadly, the book doesn't mention which was the very first LP released.
This guy Goldmark was Hungarian (I mean from Hungría, you know, the Magyars I think they're called) and worked in CBS since 1936. He received no royalties for his invention, but was named vice-president of the company in compensation (1950) and also received since a free copy of every LP issued by CBS. He died in 1977, two weeks after receiving a life achievement by then USA President Jimmy Carter.

[QUINNY]

Of course Graham if only they still did 64 minute discs we'd now have no problems whatsoever with compatability problems.Sadly it looks as if 80 minute will be the only ones available pretty soon.
In my professional life, I still trust DAT tape more than CDR, followed by Minidisc (now that the sound quality is so good). I've had more problems with CDR than any other format.
BTW I'm could now burn copies at up to 40X speed when duplicating, but tend to stick to 16X or 20X.

[BrunoRepublic]

Speaking of CD burning... the other day my NEC burner died on me, so I ran out and bought another one. Got a cheapo Sony model for $70 Cnd, and the slowest speed it will burn at is 8x -- which was the fastest that my old NEC would go!

Even now, it still amazes me how fast technology moves...

[disco1999]

I think that the new error proof burn technology available on most recent cdwriters is much more important than having the fastest burner on earth. I have lost so much CDs with errors, I have a Yamaha 8-8-24.