Brilliant

For an early devlopment design, its brilliant.

Few thigns it needs to be come usable tho, some sort of sheath, i.e., you insert the cd while closed, and then instead of just openning up a little bit, the two sides would fold all the way round the CD enclosing it in some sort of concertina-style casing - or somethign like that.

I definitely want one - and if it ripped CDs to mp3s, then it wouldn't even need redesigning.

Safety and disc speed

As a load of people have said, there were no problems with the old Sony player. No reason the surface needs to be especially flat either.

IIRC the speed a CD spins at changes as the laser moves across during playback - 200rpm while it's reading the edge, 500rpm while reading the centre (to get sufficient data past the read laser).

Safety and disc speed

As a load of people have said, there were no problems with the old Sony player. No reason the surface needs to be especially flat either.

IIRC the speed a CD spins at changes as the laser moves across during playback - 200rpm while it's reading the edge, 500rpm while reading the centre (to get sufficient data past the read laser).

WTF?

The only reason for multi-format players is to allow consumers to protect their investment in an obsolescent format. However, given that anything that is on CD can be easily and quickly ripped to MP3, I fail to see the point of this device, unless, as others have said, it allows you to rip on the go.

For regular use as a CD player it's inherently flawed - IT may be ultra-portable but a decent selection of CDs isn't.

Not all that original...

It looks a bit like a Sound Burger portable record player. You can see one on this site: http://www.retrothing.com/2005/11/sound_burger_vi.html

As someone else pointed out you couldn't put this in your pocket whilst it was playing a CD, you couldn't really listen to it in a car or on a train, and it would scratch the discs really easily. Also it looks like if you closed it whilst it was playing it would fire the disc at some speed.

Great, just needs a hanger

All it needs is a hanger.

Assuming the CD player is just to be used inside or in a car, then hanging it from somthing should bypass the accidentally hitting the spinning CD issue.

There's nothing new under the sun

Brings a whole new meaning to the phrase 'ripping a CD'. Not a new idea, however - it reminds me of a product called the Audio Technica Sound Burger. It was basically a vinyl record player that looked vaguely like an over-sized set of heated hair straighteners. You flipped it open in the middle, popped your LP in and it played it - most of the LP was left flopping around in the air like the above monstrosity. Did a pretty damn good job of destroying vinyl, as I recall...

Cool!

I thought I'd be the first to say it's "Kewl" ......not

Maybe the designer could add rotors to the top and it could hover above the users head tethered by his headphones so it won't go flying off.

On second thoughts maybe it would gain extra long distances as a frisbee...straight into the furthest bin!

Seedy

It should have a quick release button so you can shoot the cds out of the player, kinda like a cross between those helicopter rotor toys we had as kids and a ninja star :)

How cool!

A musical angle-grinder. Who would have thunk?

Re: Rubbish

How can the center of the disc spin at differnt rpm to the rest of the disc?

Seen before

I used to have a Sony D-88 Discman that would have the same effect, just sans the folding action. It's pretty nice if you just want a very transportable device, not a portable one.

ripping would be fantastic

but I mainly want one for the awesome geek-weapon potential.

"My supernature CD is going to cut you up!"

Fony

Sony did a CD player like this back in the 80's

http://www.craigbarron.co.uk/sony-d88.jpg

No more talk

There's no torque behind a spinning cd, it won't take a finger off, and most likely won't even give you a small cut, it will just stop if you touch it.

Isn't this guy a bit late to market with a transition device though, maybe 5 years ago....

NEW...

It plays MP3s, plays CDs and now works as a self defense weapon!

I wanna take one to the airport with a cd playing just to see what happens.

Title

So just how long does it take to rip the CD in the first place making this idea completely redundant ? I suppose if you can't wait to get that brand new CD home then maybe it has that use. Given that virtually everybody with an MP3 player has access to a computer, then just where is the market for this thing?

As a desgn idea it looks great, as something I would buy I can't imagine why I would do it. I'd prefer all that extra space and weight taken up by the likes of motors and read heads to be allocated to more space for memory and batteries.

For those talking about the impossibility of spinning CDs at a different RPM rates at different distances, then of course you can't do that at the same time, but it is perfectly possible to vary the RPM rate as the head tracks across the disk. Indeed this was a technique called CLV (constant linear velocity) as opposed to CAV (constant angular velocity). Audio drives were (I hink) mostly CLV, but no doubt the same behavior is now mimiced using CAV and buffering as CAV is simpler mechanically.

Call me old fashioned

Small ain't necessarily best.

Our kids lost so many MP3 players because they were so b****y small we have gone back to CD/MP3/WMA players. Result - kids embarrassed but no players lost. Excellent.

Love the third use as an angle grinder. Wonder if a diamond cutting disk would fit?

500 rpm centre, 200 rpm edge

The reason for the difference is that the track goes past the head at constant linear velocity (unlike a record player). So the motor spins the disc at 500 rpm when the head is in the centre, dropping to 200 rpm as it moves towards the outside. That's why when you stick a duff disc in you can hear the motor spinning up and down as the head seeks from the inside to the outside.

Old technology made new again

Not much new about this except the design and format of playing the mp3's, I have a portable cd player, that I have had for a couple of years now, which not only plays regular cd's, but mp3's burnt onto a cd as well. Has come in very handy on occasion.

@Luke and Ted Treen

Did you consider that perhaps the CD spins at 500rpm when reading the centre of the disc, and at 200rpm when reading the edge of the disc, in order to maintain a consistent speed past the laser?

Variable rotation speed

Stop trying to be smartarses and think about what the guy said. How could you approach this concept in such a way that it makes sense, rather than leaping to the conclusion that the poster was an idiot and then looking like one yourself?

When the player is reading data from the centre of the disk it has to spin the disk faster to maintain the same bit rate.

RE: @Rubbish

CDs rotate at different speeds depending on what part of the disk is being read, they rotate at about 500rpm when reading near the hub of the disk, and at about 180-200rpm when reading near the outer edge.

spin speed

I suspect that @Rubbish refers to the different speeds the disc spins at when reading the track near the centre of the disc and towards the edge of the disc.

to @Rubbish and Luke.........

To be fair, @Rubbish is correct, if the thing *could* make a CD rotate at 200rpm in the middle and 500rpm at the edge, then indeed it would not 'stay in one piece for long'.

But then Luke is also correct....

Ho hum, back to work .......;-)

Sure... Cut fingers

OMG, a CD running at 1x. When you touch a spinning CD it just slows down and starts to skip. The motor in there is probably consuming less than 2W. It's REALLY easy to stop a spinning CD, it's not a sharp blade with a 300W+ motor making it run at a few thousand RPMs.

Sony had a 33RPM player like that.

Speed varies while playing

The main parameters of the CD (taken from the September 1983 issue of the compact disc specification) are as follows:

Scanning velocity: 1.2–1.4 m/s (constant linear velocity) – equivalent to approximately 500 rpm at the inside of the disc, and approximately 200 rpm at the outside edge. (A disc played from beginning to end slows down during playback.)

Title

Gees CDs spin faster *reading* inner tracks than they do reading outer tracks. The drives change the disc rpm to maintain a constant linear velocity at the read head.

As for lost fingers, well if you try hard enough a CD can get about 1/4 way through a bit of 2 by 4. http://homepages.newnet.co.uk/martynarnold/aol.htm

Hmmm

And the advantage of this over portable CD players that will play MP3 from a data CD are what exactly?

@Rubbish and @Ted

You are both wrong I'm afraid, chaps. Audio CDs are read at constant linear velocity, which means that when the data is being read from the middle of the disc it must spin faster. So, going from the beginning to the end of the content, which works from the middle to the edge, the rate will indeed decrease from ~500 to ~200rpm.

CD rotation speed

@Rubbish:

CDs have rotational speeds from ~150 to ~300 RPM (~300 RPM at the centre, and ~150 RPM on the border). They use CAV (Constant Angular Velocity), hence the variation on the speed. These speeds are the original spec of CD (CD 1x). The last reader with CLV all the way up from beginning to end where the 12x units. Above it they use either CLV (Constant Angular Velocity) all the time (a 52x can, rougly, read at 28x in the beggining, growing slowly until reach 52x at the very border) or a mix of both.

@Ted Treen & Luke

He wasn't clear enough. I believe that he was saying that the disc is read at 300 RPM at the centre and 150 RPM at the border. Wich is roughly true, for a 1x reader.

"Rubbish" is right.

He means that traditional cd drives vary the speed of the motor in order to maintain a constant data read. So when the outside of the disk is being read the motor gives the disk a lower rpm than when reading the center.

Sorry chaps you may have your physics right but make sure you understand how things work before telling people they're wrong.

@me

I got the RPM wrong. Original guy was right: about 500 RPM at the centre and 200 RPM at the border. But the rest of my post was OK. :)

Don't know from where I got the 150-300 figure. Ah, well...

CD revolution rates...

Luke wrote:

"Interesting ideas about the laws of physics there Jimmy-boy... so the centre of the disc (which is fairly solid and not actually much like a fluid at all) spins round 2.5 times for every revolution the edge of the CD performs? Wrong is soo many ways.."

The disc rotates at a variable speed due to the data stored on it being at a constant density. Naturally, the disc has to be rotated faster as the optics are near the hub, because there is less data near the hub then at the outer edge. On the outer edge of the disc, the disc does not have to rotate as fast in order to get the same amount of data. Hence, the disc rotates slower.

To echo what others have said...

As a ripper, it's a great idea. As a CD player, it's rubbish.

And be fair to poor old First Posting Anonymous Coward up there - I believe he's trying to say that the thinks the RPMs vary according to the position of the read head (although he's got the concept totally backward, and so far as I know it's not correct anyway), not that the inner portion of the CD spins at a different RPM from the outer portion. So he's confused, but not totally thick.

RE: Audio Technica Soundburger

I saw someone with a similar device at a record fair last year, I suppose it's best to have a listen before you buy

Title

"Given that CDs need a nice dark environment to work and a CD spinning at around 500rpm (centre) to 200rpm (edge) this is going to be poor.

Lost fingers, music skipping and the fact that this solution is not mobile I would stay well clear."

LMFAOROFL (Sorry about that bit)

I'm sorry this is too funny/stupid to ignore!!!

If a circular object is spinning at 500rpm on the inside and 200rmp on the outside the outside is moving slower so the object has to be fluid (would look like a cyclone).

It is a solid object, the inside revolves as many times as the outside.

Secondly, you don't need dark as the red laser works fine in daylight. I have disassembled a CD drive to 'miniaturise' it in this way. Guess what? It worked fine, I could interrupt it with my fingers and it would just stop. The motor is not powerful enough to cause any kind of cut, friction burn or injury. You'd have to be very stupid/unlucky to cause yourself any kind of injury with it.

With a good buffer, you don' need to worry about skipping, only scratches. I tested this too with my disassembled player. Took 40 seconds of complete stoppage to skip with the buffer enabled. I could start and stop it without adding up to 40 seconds and it would be fine.

@luke

cd's slow down when the lens is reading from the edge (or is it centre? - i think it's the centre because dvd±rw drives get their peak burn speed near the edge of the disk).

i don't think "rubbish" meant that the two speeds would be simultaneous!

also, i don't think this would cut anything - more likely jolt to a stop and damage it's motor or even lens mechanism!

Brilliant, but not entirely unprecedented

I like it, a little lateral thinking is always worth a whirl. But something similar was done before. Hiding in a dark cupboard somewhere I have a tiny record player made by Mullard (I most of you old enough to remember the name thought they

only made transistors).

It's about the size of two of the original Nokia 9000s side-by-side and only a fraction of the size of an LP; remember them, 12" in diameter & made of vinyl?

The pickup was off to one side and the player could be opened out to reveal a small spindle and a little rubber wheel which ran on the underside of the record to rotate it. The audio came from a 3" speaker driven by a small transistor amp with the whole thing powered by a couple of D cells.

Very portable, but back then playing LPs in your pocket didn't really arise.

Niall

Been done before

I seem to remember 3" CD players being available about 15 years ago with a similar ability to play the larger normal size CDs. Yawn.

Has there been a timeslip ...

... to 1 April?!!

Re: Different speeds on diferent disk areas

Because of the increase in linear (not angular that is constant) velocity the further you get from the axis of rotation, a single-speed audio cd player reduces the rate of rotation as the read head moves from the center to the edge of the disk. This is to maintain a constant relative linear speed between the disk and the read head.

IIRC, multi-speed readers (such as that nifty 50x cd-rom drive in your computer) are designed to be able to read the data faster (they have a faster internal bus) so this slowing is not as necessary. (I could be completely mistaken on that second point, though)

external CD spinning ?

What I want is the ability to launch the CDs

Now thats what I call CD ripping

nostalgic ex-Tribes player

How about an extra casing with a fan function

...for those hot days

So while you listen to your MP3's you can get the breeze of the music... ehmmm errr... spin.

Am I dreaming ? =P

I would SO buy one of these

...it's not that it has to be overly practical to play CDs on the move, but it'd be great to have the option for if you're on a train or at someone's place. Especially if it could rip the CD to the MP3 player for you. It'd have to come with a lot of memory of course and perhaps play MP3s from DVD-R if you inserted one in to the unit. Then it'd be a well cool gadget.

Portalbe ripper

It would be useful as a portable ripper, if you were visitng a friend.

More RPM crap/pedantry

Late to this but couldn't help read a list of almost 100 comments ;-)

I'm quite amazed that no-one has picked up on a couple of posters here, namely Luke and Marcelo Rodrigue. RPM is a measure of Angular Velocity, so if the rpm changes then so has the angular velocity - 1 rpm = PI rad/min after all.

As the first poster, there is nothing there to indicate that they are referring to that fact that audio CDs are read at CLV rather than CAV. It has either been assumed that the reader knew this (and could therefore decode the writing) or that the author had read the figures somewhere and not questioned that a rigid body could act like a fluid.

Case design

Someone mentioned that the case splitting in two doesn't actually make more room for the CD to fit.

But surely it does create a much more stable device that can be placed flat on a table. Otherwise it would tip sideways and damage the disc edges.

I don't really think it's designed to play CDs while in a pocket. Even then, since when does a CD have a razor-sharp edge? Nobody could possibly be injured by this.

Been done before

I've seen similar designs before.

Anyway, who in the hell uses discs anymore?

But the REAL question is...

Will it BLEND?

Coat donned...