Best conversion of old CD's to lossless?

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How can people believe these crazy theories? I have tested many discs and none ever had a problem caused by magnetism.

The optical focus and positioning lens are very strong affected by any magnetic field.
The content of the toner used in CD printing is at least 40% iron oxide and indeed will get magnetized over time by CD puck magnet and also by magnets used in optical drive.

You can test this using plextor tools and see C1 and C2 errors of a CD before and after magnetization.

Regards,
Tibi
 
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You can patent nearly anything, doesn't necessarily make it technically valid and that particular patent seems to have expired.
Not to mention a CD has no ferrous material to be magnetised. Plus the required magnetism to upset the laser tracking mechanism wouldn't be possible from the CD label (if you believe the patent).

If the product of the patent does not give the applicant substantial income, he should have given up maintaining the patent. However, if you go to the USPTO to find out, you will find that the patent has been paid for 20 consecutive years, and the patent maintenance fee is getting more and more expensive. By the 11th year, the annual maintenance fee is as high as USD 7,400. Even if a rich man will not pay 7,400 to the US government for no reason.

USPTO Fee Schedule | USPTO

If your equipment and ears are sensitive enough, you will hear the help of Demagnetizer for the sound. It is up to you to believe or not to believe that you should pursue a little better. However, don't try it yourself, or your equipment and ears are not sensitive enough to deny others' technology.
 
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My CD Cats analyzer is extremely sensitive and very revealing.

There is also a more crazy Demagnetize technique, as long as a CD with a special sound is played, it can eliminate the magnetic in the sound system. This special CD is also the product of the audio manufacturer Densen. It's hard to explain why it works, but it really works.

Densen Audio Technologies - Densen Audio Technologies DeMagic Demagnatizing CD by Densen Audio Technologies - Amazon.com Music

T317050a_600x600.jpg
 
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This is why magnetism is not a problem in CD's:

Reed–Solomon coding is a key component of the compact disc. The result is a CIRC that can completely correct error bursts up to 4000 bits, or about 2.5 mm on the disc surface. This code is so strong that most CD playback errors are almost certainly caused by tracking errors that cause the laser to jump track, not by uncorrectable error bursts.
 
This is why magnetism is not a problem in CD's:

Reed–Solomon coding is a key component of the compact disc. The result is a CIRC that can completely correct error bursts up to 4000 bits, or about 2.5 mm on the disc surface. This code is so strong that most CD playback errors are almost certainly caused by tracking errors that cause the laser to jump track, not by uncorrectable error bursts.

For audio equipment, there are a lot of strange props that can't be explained, such as the grounding box, but they really work. Speaking of a bunch of theories is not very meaningful, or actually take action, use your own ears to verify, whether it works.
 
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Reed–Solomon coding is a key component of the compact disc. The result is a CIRC that can completely correct error bursts up to 4000 bits, or about 2.5 mm on the disc surface.

This is very true, but any error correction is translated in jitter. Some DSP's will correct faster than others, but when you deal with 100s or 1000s errors things become very easily audible.

Regards,
Tibi
 
Mark,

I do not know what you mean by "workload", but I know that any DSP operation need one or more clock cycles. Once an error is detected, correction start and an arithmetic operation is performed. Each operation take several clock cycles. Think on this.

Regards,
Tibi

There is no dsp involved in error correction. Google for hash function and checksum algorithms.



Question: How do you magnatise plastic, aluminum and a bit of paint?
 
There is no dsp involved in error correction. Google for hash function and checksum algorithms.
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From attached DSP datasheet. You may try other chips as well.

"Overview
The LC78601E CMOS IC implements compact disc
player signal processing, servo control, LCD display, key
input acquisition, and remote controller processing
without requiring control by a separate microcontroller.
The basic functions provided include demodulation of the
EFM signal from the optical pickup, deinterleaving, error
detection and correction,
8× oversampling digital filters,
D/A converter (with built-in analog low-pass filter), LCD
driver, remote controller processing, key acquisition, and
control processing. Thus this IC can provide excellent
cost/performance characteristics when implementing a
low-end CD player."

I already explained above that toner used in CD printing have more than 40% iron oxide.

Regards,
Tibi
 

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ofswitched said:
You should first learn about PIONEER's PureRead4+ technology before you come to comment.
Data transfer is either perfect or abandoned. You may be able to tell it how hard to try (e.g. how often to retry) before giving up.

However, if the cd driver is always in error due to vibration, power supply and other factors, and is still in the same place, no matter how good the software technology is, it is impossible to know whether it is wrong.
The chance of false data being accepted as valid data is vanishingly small, unless the reader is astonishingly poorly designed.

For a CD that has been read more than ten times, in fact, his surface will be magnetic, causing the CD driver to read errors, and need to be demagnetized.
Not even wrong!

This is not Mystery, it has been verified, otherwise Acoustic Revive's Demagnetizer will not be sold for twenty years.
To sell something you just have to convince ignorant people that there is a problem which it solves. The problem does not have to be real.

It can be seen that your audio equipment and ears are not very sensitive.
It can be seen that your critical faculties and knowledge of science is not very sensitive.

For audio equipment, there are a lot of strange props that can't be explained, such as the grounding box, but they really work.
Now you are being funny.

tvicol said:
This is very true, but any error correction is translated in jitter. Some DSP's will correct faster than others, but when you deal with 100s or 1000s errors things become very easily audible.
My understanding is that most, if not all, the error correction takes place as a natural part of the decoding so raw data with errors flows in one end and processed data without errors emerges at the other end. In any case, the data ends up in a FIFO buffer and is then clocked out to the DAC. There is not a little man inside who has to run off to another department to get some data checked and corrected when an error occurs, thus holding up the process until he returns.

Is this thread now an attempt at breaking the record for number of myths per page?
 
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My understanding is that most, if not all, the error correction takes place as a natural part of the decoding so raw data with errors flows in one end and processed data without errors emerges at the other end. In any case, the data ends up in a FIFO buffer and is then clocked out to the DAC. There is not a little man inside who has to run off to another department to get some data checked and corrected when an error occurs, thus holding up the process until he returns.

Is this thread now an attempt at breaking the record for number of myths per page?

Yes, error correction is a "natural part", but correcting the wrong bits is a process that add more extra clock cycles. Even you move from buffer to buffer, register to register, this not happen by magic. There is a clock to follow for each operation.

FIFO buffer and reclocking is another story.

Regards,
Tibi
 
Yes it's hardware, but still there is an ALU (Arithmetical logic UNIT) that is clocked by and external clock. I think the best explanation is in SAA7210 decoder chip. Read at page 8 Flag Processing.

Regards,
Tibi
 

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OK there is a very tight hard coded arithmetic unit for performing a very specific calculation in a known amount of time (as the number of errors allowed is limited). This is all FIFO buffered so I see zero evidence of a jitter issue here in real time playback. For ripping, which is what this thread is about there is even less of an issue as you can read the track as many times as you want.



I am afraid I still view this as bucket of FUD.
 
Yes, error correction is a "natural part", but correcting the wrong bits is a process that add more extra clock cycles.
No it doesn't. Every bit goes through the same process, no jitter is introduced in this manner. Edit: See the last pdf you supplied.
Google hash functions and checksum algorithms.



Metal in paint doesn't mean it reacts to magnetic fields. Only paint with pure ferrous metal in it can be magnatized. And that is ultra rare.
 
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