What is the dynamic range and S/N ratio of CD format?

compact disc, dacs, mp3 players and streaming audio
Hanuman
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Re: What is the dynamic range and S/N ratio of CD format?

Post by Hanuman » 09 Nov 2019 15:47

NOYB wrote:
09 Nov 2019 09:02
The practical useful dynamic range decreases as frequency decreases due to the relationship between frequency and sampling rate.
How does that work?

NOYB
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Re: What is the dynamic range and S/N ratio of CD format?

Post by NOYB » 10 Nov 2019 03:20

Erin1 wrote:
09 Nov 2019 12:20
NOYB wrote:
09 Nov 2019 11:17

How does two's complement explain that I'm going wrong?
Well, everyone else in the world calculates 96dB signal to noise. That's what I was taught at electronics school. I passed the test too!

The link I provided you earlier explains it.

You're obviously going wrong somewhere.
Who in the world is not calculating 96 db signal to noise? Certainly not me. I said much earlier in this thread that the SQNR is 96 db.

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Re: What is the dynamic range and S/N ratio of CD format?

Post by NOYB » 10 Nov 2019 03:23

Hanuman wrote:
09 Nov 2019 15:47
NOYB wrote:
09 Nov 2019 09:02
The practical useful dynamic range decreases as frequency decreases due to the relationship between frequency and sampling rate.
How does that work?
Missspoke there. It has nothing to do with finished product CD. Has to do with recording, mixing and editing. For instance increasing the volume of a very weak signal.

A 40 Hz signal covers the span of 1102 samples (44100/400 = 1102.5). If the signal level is low enough, say -50 db, the amplitude of the low frequency wave form does not rise and fall fast enough to prevent large blocks of consecutive identical samples due to the quantization granularity. If the frequency and signal level are low enough it can end up being more like a square wave.

But of course studios etc. don't work in the 44.1 KHz 16-bit realm. Though given the right combination of signal level, frequency and sampling rate it could be experienced even with 192 KHz 24-bit.

Hanuman
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Re: What is the dynamic range and S/N ratio of CD format?

Post by Hanuman » 10 Nov 2019 03:31

NOYB wrote:
10 Nov 2019 03:23
If the signal level is low enough, say -50 db, the amplitude of the low frequency wave form does not rise and fall fast enough to prevent large blocks of consecutive identical samples due to the quantization granularity.
Yes, that's loss of resolution, confirmed by a composer/engineer friend of mine as a real thing back in the day, with emphasis on "the day" since 16-bit production started to disappear in the nineties. I don't think it's dependent on frequency BTW.
Last edited by Hanuman on 10 Nov 2019 03:50, edited 1 time in total.

GuidoK
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Re: What is the dynamic range and S/N ratio of CD format?

Post by GuidoK » 10 Nov 2019 03:37

Erin1 wrote:
09 Nov 2019 12:20
Well, everyone else in the world calculates 96dB signal to noise. That's what I was taught at electronics school. I passed the test too!
This is a double fallacy (argumentum ad verecundiam and argumentum ad populum)

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Re: What is the dynamic range and S/N ratio of CD format?

Post by NOYB » 10 Nov 2019 04:51

Hanuman wrote:
10 Nov 2019 03:31
NOYB wrote:
10 Nov 2019 03:23
If the signal level is low enough, say -50 db, the amplitude of the low frequency wave form does not rise and fall fast enough to prevent large blocks of consecutive identical samples due to the quantization granularity.
Yes, that's loss of resolution, confirmed by a composer/engineer friend of mine as a real thing back in the day, with emphasis on "the day" since 16-bit production started to disappear in the nineties. I don't think it's dependent on frequency BTW.
I believe it occurs at all frequencies below the Nyquist frequency and is exacerbated as the signal frequency goes lower due to the increasing amount of quantization errors per cycle as frequency decreases.

Though this isn't really pertinent to the subject of this thread and thus it was a mistake on my part to injected it.