Why people buy 100$ HDMI cables

[Purple Sunray]

Inspired from another thread, I would like to shitstorm an artice about CD ripping.

IMHO this is the kind of stuff vendors tell ppl to make them buy the 100$ HDMI cable instead of the 10$ one

(we all know it is because the 100$ one will make the picture look birgther, with more contrast and better colors)

 

http://www.coreaudiotechnology.com/ripping-a-good-one-the-technicalities-of-cd-ripping/

 

For those who dont know, RIP is the term used to take data from a CD and transform it for playback on the computer as a file. These files are stored on the hard drive along with album meta data, cover art, track titles, and so on. This keeps tracks organized for easy access later on through your favorite computer-based playback software.

Agreed

 

A digital signal is a square wave. A square wave is an analog representation of a digital signal. On a CD you have an imprinted square wave. This is important to understand, because this is where your distortion manifests itself.

No, a digital signal is no square wave. Forget that shit. Now.

A digtial (also called discrete) signal is a sequence of values that represent an analog (also called continuous) signal. Rember that one.

 

Remember how obsessed we at Core are about power supplies? If not, now you know. So should you be. Power from the power supply is used to generate the laser that reads the square wave. This square wave contains voltage data, which is, in theory, either a 0V or 3.3V pulse.

Agreed

 

In a ripping system you have a piece of software that is designed to do this process for you on a particular operating system. Why do different pieces of software make a difference? Algorithms (mathematical gymnastics).

Agreed

 

Every algorithm is different and every algorithm results in a different rip.

Not necessarily.

 

If there is no problem with the original CD, there is no algorithm required to process the audio data.

The format stored on CD is 44.1kHz 16bit PCM, which can be converted to .wav by wirting a couple of bytes (WAV RIFF header) before the actual audio data.

So this is a 1:1 copy, no algorithm involved.

 

If there is a problem with the original CD, there is audio data missing because of bad sectors (read errors).

Now the algorithms come into the game, there are 2 basic types of it:

ECC and custom algorithms.

ECC is metadata which is stored on the CD. By using this metadata, a software can prefectly reconstruct the missing data. Like a 1:1 copy.

Most Audio CDs do not have ECC.

So what most players do if they face a read error, is to mute during the missing part. The well known suttering.

Software can include algorithms to interpolate the missing piece.

There are various ways of doing such an interpolation which range from "pick the middle value" (linear interpolation) to perfect reconstruction (bandlimented sinc).

This algorithms will not degrade sound quality of data that can be correctly read from the CD.

They help you to re-construct audio data where the CD cannot be read, but they are NOT always on.

[Purple Sunray]

This is because algorithms are basically guesswork based on math. Its like guessing all Cs on your scantron, and we all know how well that goes.

Bullshit, see above.

 

Look at the concept of error correction. It uses interpolation (guesswork) to input data that the algorithm thinks missing. Interpolation picks a random point between two existing points and inserts data that doesnt exist. Nuff said?

Again, see above.

Error correction will not change the signal where there is no error.

 

Lets say we have perfect algorithms, whatever that means. These algorithms are processed by the CPU in real time. For the CPU to process data it must first be loaded into memory. Bottleneck alert! (If you havent done so yet, read our article on the RAM and CPU relationship, it will explain this bottleneck in more detail).

Holy shit.. rly?

Your 44,1kHz 16bit stereo signal has a data rate of:

16bit = 2byte

2byte * 2 channel = 4byte

4byte * 44100 sample per second = 176400 byte per second

So you are telling me that tranferring 172kB of data per second from RAM to CPU is a bottleneck?

Ok, to be fair, let's rip 32x.

So this are 5.5MB per second.. between RAM and CPU.. bottleneck. .... seriously?

My i7 system does 62GB per second

 

Ill simplify this down to speed of processing. When the algorithms are not processed quickly enough latency occurs and the data floats in limbo waiting to be processed. During this time the square wave picks up noise, which causes amplitude distortion. All noise carries a voltage, albeit small, that adds or subtracts from the voltage in the square wave. The resulting amplitudes are imprinted on the resulting file and the resulting distortion becomes your music. Permanently. Timing can be fixed, amplitude cannot.

Sorry, but I cannot shitstorm on this, because I do not understand what he is talking about.

What noise?

This is how ripping with humans works:

There is one guy reading data from CD, writing it to a paper and putting this paper into a box (buffer).

That box is called a FIFO (first-in-first-out) buffer. First paper put in, will be pulled out by the other guy first.

The other guy reads from the paper and writes that data to the ripped file on the disc.

If your system (one of thoses guys) is not fast enough, the box will become full and the other guy needs to wait.

In your example the data waits on the limbo (aka FIFO), so the one that reads the papers and writes to file is not fast enough.

That also means, that one that reads from the CD needs to read slower, cuz limbo aka FIFO is full.

It's that simple.

There is no noise.

 

..

The power supply is what creates the 0 and 3.3V peaks of the square wave that determines your sound and digital signal. The amplitude of the square wave determines the frequency and harmonic content of your music.

This is just plain wrong.

 

The amplitude of a digital signal doesn't mean anythnig.

There is low threshold and a high threshold.

If the amplitude is below the low threshold, is called a LOW level, or 0.

If the amplitude is above the high threshold, is called a HIGH level, or 1.

 

Do you still rember the one to rember from above?

No? WTF

Again:

A discrete (digtial) signal is a sequence of values that represent a continuous (analog) signal.

 

Lets start vice versa, with the analog one.

There is nice psy squelch on an analog signal, which you want to convert to digital.

To do that use a device a called Analog-to-Digital converter.

That device looks at the squelch signal at certain intervals, and stores the current ampliutde value as a digial value.

For CDs, this converter will look at the singal 44100 times per second and store the value as a 16bit number.

.. I could do an introductoin to the sampling theorem now (Nyquist) but that's not the point.. I want to shitstorm

The point is that the amplitude of the low/high pulses, that describe the digital numbers, don't have anything todo with the frequency of the psy squelch ..

 

 

...

I must say that I lost the track completly now.. I just don't understand what he is talking about, so it's hard to flame it..

 

 

 

Anyway.. hope you got my point... next time buy the 10$ one.

[Rotwang]

Error correction will not change the signal where there is no error.

I gather you know more about this than I so correct me if the following is wrong...

 

It's worth adding that, most of the time, error correction will not change the signal even if there are errors. That's because of coding schemes that can be used to reconstruct the original signal if there are fewer than a certain number of errors per block. See here for an example of how this works.

[Veracohr]

While I agree with you 100%, why are you posting this here instead of telling the authors?

 

My opinion is to let the people who are duped by this shit have their illusions. They apparently have money to burn and not enough to occupy their time so let them contribute to the economy by buying stupid shit.

[Purple Sunray]

While I agree with you 100%, why are you posting this here instead of telling the authors?

I would actualy do that if it would be some brainstorm could-be student blog.

But this is a company that runs a buiness based on fanatisy physics.

I assume they just laugh at me if I write them (yeah yeah we know, but don't tell anyone).

So I prefer to write to the other end of the moneh train

I'm no activitst.. just tech freak xD

Feel free to post that on their facebook page, will bring some traffic to psynews page

[Redo]

.

[Purple Sunray]

You are the idiot, 1001$ cable would have also included background radiation compensation

[abasio]

I have a £5000 cable and it just makes the ladies so horny. Chicks dig high end audio, especially cables! Best 5 grand ever spent.

[Purple Sunray]

ahahah I actually did it.. I sent them an e-mail.. xD

But I do not really expect an answer.. =)

 

here it is:

 

 

Hi.

I did not want to write this email at all at a first place, but a colleague convinced me to do it.
A couple of days ago I joined a discussion about CDs on a music forum (www.psynews.org).
One member was recommending to not use CDs, because they basically are the same technology as vinyl (where signal amplitude actually has a correlation to the signal frequency).
But they are not, CDs are digital.
Since that user started to seriously defend his idea of how CDs work, I was wondering from where he got that information.
He pointed me to your page.

So long story short...
if you are a business guy and just don't know about that the tech stuff on your blogs is plain wrong, remove it from your page.
Everyone that has enough technical knowlege to understand what you are writing about, will think that this business is only about to rip off peapole that do not understand what you writing about. Given that fact, I would discourage peapole to buy from you. So might be better just remove the articles and not get bad reputation...
If that was actually your hidden plan, have fun.. I do not really care about your "business" model.
Anyway, I did a "review" of one of your blogs. It was just to show to that user how much bullshit is in there.
https://www.psynews.org/forums/topic/71900-why-people-buy-100-hdmi-cables/

Yes, power supply is important. But for very different reasons like described by you.
And yes, there are lot of things that can wrong during CD ripping. But this are not the things you write about.

So if you are interested to learn about that stuff and fix your blogs, I can point you to the right resources (digital technology basics, CD Audio Red-Book standard, Nyquist sampling theorem, Cross-interleaved Reed-Solomon aka CIRC - that the is stuff you need to understand to explain your ripping system).
If you are not interested .. I do know the reason for it already and do not really expect an answer on this.

peace

[abasio]

Haha, I'd like to see if they respond.

[Rotwang]

The audiophile snake oil rabbit hole goes pretty deep

[abasio]

What the hell are they supposed to do?