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by sramsay 1926 days ago
Saying "CDs have too much treble" is like saying "books have too many adjectives."

And no, for millionth time. Per the Nyquist theorem, the waveform being generated is identical -- the same, without any difference whatsoever -- when the sample rate is twice the frequency being reproduced. Which it is, because the sample rate of a CD is more than twice the theoretical upper range of human hearing.

You can talk about aliasing if you like. I see some people in the thread with super-human hearing can detect the buzz of CD drive motors. But this "digital is not as good because it's discrete and audio is continuous" is complete nonsense.

If you are thinking that the "digital waveforms" (?) coming out of your speakers don't sound as good because they're not continuous, or "choppy," or missing information . . . you're really not making any sense at all.

3 comments

Please omit swipes like "for millionth time" and "you're really not making any sense at all" from comments here, regardless of how wrong someone is or you feel they are.

https://news.ycombinator.com/newsguidelines.html

Even just getting a decent DAC can make a lot of difference. There's a difference between playing a CD on a decent setup or a cheap portable player with 5$ headphones, shitty cheap DAC and sloppy electronics. With the right software, you can even emulate a lot of distortion and warmth of analog equipment even. Some more expensive consumer grade hardware (Bose is a good example) takes a lot of liberty with processing the sound that gets send to the speakers.

It's basically the same as iphone owners claiming their cameras are better because they get such nice crisp colorful photos. Which depends on roughly the same kind of lossy algorithms that electronics manufacturers use to make cheap hardware sound awesome. Compress, filter, boost, etc. It's a lossy process. It's intentionally losing recorded detail for the effect. The audio equivalent would be the wall of sound type sound associated with 1980s pop music. Sounds great on a cheap brand walkman ripoff (went through several in the 80s).

CD recordings have historically been optimized for cheap equipment and FM radio. The storage medium is not the problem: the sound is intentionally compromised when the master is created already. That's why remastered recordings are a big deal these days and also why a lot of LPs sound better (different master, generally better equipment used for playback). Same recording, but a better masters optimized for different purposes. One sounds better than the other but people get confused about why that is.

> the wall of sound type sound associated with 1980s pop music

"Wall of Sound" recordings are primarily from the 1960s. "Pet Sounds" by The Beach Boys is the quintessential recording in the style.

https://en.wikipedia.org/wiki/Wall_of_Sound

See: Analog vs Digital[1].

I said there were differences. A lot of people putting words into my mouth.

I was actually alive and aware listening to pre-1980s vinyls, 8-tracks, cassettes, CDs, etc. unlike some of you. CDs added additional frequencies into the high range, which people thought sounded crisp and new, but it never had the warmth of cassettes and vinyl.

The waveform thing is true but I never said that it was the reason for the difference in warmth.

[1]- https://innersense-inc.com/analog-versus-digital/

Right. I was actually alive too. What we're trying to tell you, is that the kind of explanation offered in that article is absolute bullshit. It's common! People make this kind of argument all the time. It's still wrong, for the reasons eloquently outlined in the replies.

I think the thing that trips people up is that they think that a digital process can somehow fail to make something happen to an analogue speaker cone that an analog process can do effortlessly because of the nature of the process (or the medium). It's not true.

Do you like vinyl better? Or CDs better? Or reel-to-reel tape? You'll get no argument from me, because "better" is a pretty subjective thing. But the following propositions are absurd:

1. Vinyl has "higher fidelity" than CDs. 2. CDs "add treble" to recordings. 3. Digital processes can never accurately reproduce analog phenomena. 4. Analog "warmth" is only achievable with analog equipment. 5. No one ever over-compressed their tracks until CDs (or Pro Tools, or DAT tapes, or whatever) came along, and so these things are to blame.

I could go on.

I'm not accusing you of having said all of these things; they're just examples of things are absolutely not true, but which get said all the time, and which start to seem like truth because everyone is nodding.

CDs do emit music over higher frequencies stronger than vinyl. That is not a lie.

The lies about lies are lies.

Some people can’t hear it. I can. I can hear a TV when it’s on, and I can hear harmonics of Wifi, so when I say I know it’s true- I know it’s true.

They -can- emit higher frequencies with better fidelity (and DR), however that's a product of mastering the CD, not something that need occur in the CD by its very nature. So the way you're stating it is incorrect. A CD can replicate anything a cassette/vinyl can do (that is perceptible by human hearing). Now whether industry respects that or not is up to the company/band/whatever making the CD and what they choose to emphasize.
And I know Wifi is electromagnetic radiation, so there must be some phonon interaction somehow.
I didn't look at the Innersense article until after I had written what I have below, but a quick skim shows the vendor/author is a complete digital audio enthusiast.

I like both digital and analog.

But there's always some analog distortion in your recording and playback process.

It's worth looking at the ocilloscope to compare the type of distortion that square waves give which does not appear from sine waves having the same amplitude.

The ideal thing about digital is the recording can be very accurately reproduced, vastly more so than analog media, and can be duplicated without degradation.

While being recorded with significant analog distortion (like intentional fuzz guitar or the occasional unintentional mic overload) or not, the signal is digitized as good as the ADC can accomplish.

But when you've got a bit of analog square wave coming in to the ADC to begin with, the overshoots are too narrow to be accurately captured by mere 44.1Khz sampling.

People who can tell the difference between different playback DAC's can also figure they could probably tell the difference between different recording ADC's if they were involved with the recording process.

While all of these digital electronics of course meets or exceeds Nyquist margins and Shannon's minimums.

But some people hear the difference between them anyway. Isn't that supposed to be theoretically impossible?

Some really clean, high-fidelity, wide-dynamic-range digital recordings (ideally material that is espcially _easy_ to record) can be good reference tracks for comparing systems.

So beautiful.

Then take not-so-clean but excellent sounding reference material having the same functional amplitude going into a particular DAC.

Sounds a bit worse as expected but in different ways than the pure analog _analog_ of this type listening test.

Because analog components like transistors are not perfect, but that's what ADC's & DAC's consist of anyway. Lots & lots more transistors in the signal path compared to simple pure analog gear.

It has always helped to carefully select vacuum tubes and audio transistors too when they came along.

Looks like the tradititon continues with different audiophiles preferring to carefullly scrutinize the DAC chips they have today.

Also, anybody else ever see audible subharmonics on the scope resulting from the beat notes generated by two different frequencies above the range of human hearing? One of the frequencies which is sometimes 44.1Khz.

> CDs added additional frequencies into the high range, which people thought sounded crisp and new, but it never had the warmth of cassettes and vinyl.

Sure, there is an audible difference between digital audio and vintage analog equipment — but it has nothing to do with quality problems in digital audio. In fact, it’s exactly the opposite: vinyl and cassettes deliver low-quality, heavily distorted audio (with a dynamic range equivalent to that of 5 or 6 bit digital audio). This does create a distinctive “warm” tone, and a lot of people really like the sound (or the nostalgia) created by this distortion.

The article you linked does not demonstrate quality problems with digital audio; it is a bunch of nonsense intended to sell a product.

First of all, it compares a “digital square wave” with an “analog sine wave”, and remarks that “the digital signal does not follow the smooth flow of its analog compliment.” Of course they look different, they’re not the same wave! A square wave is “supposed” to look blocky, it’s not a digital vs. analog thing.

At least it mentions the Shannon-Nyquist theorem and gets one thing right: “there is no difference whatsoever between an analog sine wave and a digital one”

But then it totally blows it again with its comparison of a “digital” square wave to a “natural” one, observing that the “natural” square wave is more curved.

Again, this is nonsense because you’re not comparing the same wave! The “digital” image is of an ideal, mathematically pure square wave, whereas the “natural” image is bandlimited. The first mathematically pure wave cannot exist in the real world, because it would require infinite bandwidth — the voltage would have to change instantly.

In fact, a digital signal is bandlimited; it’s just a bad illustration. The digital square wave, when converted to analog, will not include any frequencies above half the sampling rate, making it match whatever our bandlimited analog signal is supposed to look like.

Then the article goes into full-on snake oil mode, trying to convince you that “technology that resolves that problem, by creating infinite phase, is currently available” if only you buy their “Sensorium™ LSV III Function Generators and Altitudinal Oscillators [that] utilize a polynomial transition region algorithm”. This is very much nonsense; by the Nyquist-Shannon sampling theorem, you can reproduce a bandlimited waveform exactly from a sampled signal, no matter how “complex” your waveform is.

For a more detailed overview about how and why digital audio works, I recommend this video: https://xiph.org/video/vid2.shtml

> Then the article goes into full-on snake oil mode, trying to convince you that “technology that resolves that problem, by creating infinite phase, is currently available” if only you buy their “Sensorium™ LSV III Function Generators and Altitudinal Oscillators [that] utilize a polynomial transition region algorithm”.

Definitely my favorite part. It's complete gibberish, but because it uses audio nerd words (phase, oscillator, function generator) it sounds like it might not be.

> CDs added additional frequencies into the high range

CDs didn't add anything. The treble was always there, or was added in mixing/mastering for creative reasons. Vinyl and Cassete simply didn't or couldn't reproduce those frequencies.

You could, of course, remove the frequencies on CD to match Vinyl or Cassette, but they were kept (or even added) in CD for artistic reasons.