The development of the CD stretches back to 1979 when Sony and Philips established an engineering team to create a disc capable of stopring music in digital form. According to Philips, the original design spec called for a 11.5cm-diameter disc capable of holding an hour's music, but this was later extended to 12cm and 74m minutes - sufficient to accomodate the whole of Beethoven's 9th Symphony. Some writers claim this was driven by Sony co-founder Akio Morita, in order to ensure his favourite symphony could be stored on a single disc.
Philips' Joop Sinjou introduces the CD in 1979
In June 1980, the development specification was frozen and enshrined in what the partners called the Red Book. Later, the arrival of the Yellow Book would see the publication of the CD-Rom specification for computer use.
It might be assumed that the CD's digital encoding is sufficient to ensure perfect fidelity. Not so. Poor laser focusing, discs that wobble as they spin introduce noise into the signal, and the inevitable dust and fingerprints that accumulate on the surface, forcing the format's developers to come up with some clever error-correction technology to compensate. Indeed, listen to a disc without the special encoding, and there's almost as much hiss as music, and arguably worse than the sound produced by cassette tape.
Pink Floyd's Dark Side of the Moon: own, dedicated CD plant?
To get around the problem, CD uses a technique called eight-fourteen modulation (EFM) developed by Dutch digital recording boffin Kornelis Antonie Schouhamer Immink. The data stream is broken into blocks, each eight bits long - and half of the 16 bits used to encode the sample of the soundwave taken 44,100 times a second. The eight-bit block is matched against a list of possible bit patterns and a 14-bit code read off the table, hence eight-fourteen.
COMMENTS
I Know It's A Bit Late But.........
cd 25 years old being phased out
vinyl donkeys years old still around and has a huge following
vinyl has won
no argument
also nothing beats shaped/picture/transparent/all 3 disks
Best amps made
Some of the best transistor amplifiers you will find are the ones made in the days when they had to compete with valves. Come to think of it, even the valve amps made in those days were better, because they were competing with transistors. (My old valve amp -- ECC83 and two ECL82s per channel in class AB1, feedback via secondary of output transformer -- really doesn't like MP3s at all. I thought it was just a very bad case of tube fatigue, but a CD sounded fine through it.)
I guess it's true; when you've got nothing to prove anymore, you don't try as hard.
I made some rips from analogue cassettes and LPs, but they were always marred by noise. I eventually cured this by getting a USB mixer (i.e. with integral sound card); it has its own power supply, and so is not sharing with the computer. There's no proper RIAA equalisation, but there are separate treble, middle and bass controls for each channel and I found a reasonable setting by trial and error.
The LP record, imperfect as it is, needs to be viewed in context as part of the entire system for delivering sound from the performer to the listener. The distortions introduced by the recording and playback of vinyl records are expected by the listener, and "vinyl noise" is an integral part of the listening experience. This is not something you can expect kids who've never grown up with it to understand.
@Cliff: Piano rolls do still exist, only they're called Midi files nowadays.
@Vulpes Vulpes: You're dead right; CD boxes are no good for skinning up on. Perhaps that explains why today's youth are so into bongs.
Cheap CD players are still naff
Because of the Nyquist filter. You can't just pipe the output of the D-to-A converter to your amplifier, you need to filter off the sampling artifacts, and remove the ultrasonic content which can cause some amps to give you high-frequency intermodulation distortion. CD players have had various schemes for doing this ("1-bit converter", "n-times-oversampling" "DSP" etc.,etc) but cheaper or more poorly designed ones don't perform this well. Also, the nature of the filters can give you a high-end frequency response that isn't flat, and do nasty things to the phase as well.
The upshot of this is the well-known "listener fatigue" effect of listening to some CD players. What you are experiencing is the high-frequency distortions, which you can't consciously identify, giving a subtle jangly effect to vocals, cymbals and other "tizzy" stuff.
The effect is made more horrible by the tendency for modern music CD's to have gallons of treble boost applied, to make the music stand out on small radios and in clubs. Yuk.
What about the 3 sided LP?
Monty Python released a 3 sided LP once. One side had 2 concentric tracks so you randomly got one of the two tracks depending upon whichever the needle picked up on the lead-in.
Try doing that with a CD, MP3 or other digital format...
LP -> CD improves quality
I've just had a hundred ancient LPs transferred to CD for my father (87). He is utterly amazed at the huge improvement in quality. He believes that they sound better than the original LP when new.
Of course the transfer was done with a first rate turntable on newly cleaned records with attention paid to get the proper balance. He has a really cruddy twenty year old turntable with the same needle it was bought with.
It is amazing that the LPs are in good enough condition to produce the copies - but I must say that I agree that the quality is extremely good, now that they are transferred to CD. This is probably the best solution - play LPs once, onto CD....
