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  #11  
Old 02-09-2002, 08:31 PM
Doc Doc is offline
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Default Re: sample rates...44.1 or 48...what do you use?

Park,
My understanding of Nyquest is the same.
Perhaps my last post was a little misleading. Something I should add is that a complex waveform at the high end of the audio spectrum will actually contain harmonics outside the audio (assuming 20Hz-20KHz) spectrum.

What I was implying is that the 192KHz system will more accurately reproduce the complexities of this waveform but the human ear most likely won't hear the difference if it can't reproduce the harmonics that create the complex waveform. It will hear the same thing that the 44.1K system can reproduce.
In fact the 44.1K system is most likely to be more accurate in this area than a human ear (Unless you can hear above 22.05KHz).
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  #12  
Old 02-10-2002, 12:48 AM
Doc Doc is offline
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Default Re: sample rates...44.1 or 48...what do you use?

Park,

I agree with you and Chompers 100 percent regarding 44.1K vs 48K.
Your points about 44.1K vs 192K are very interesting food for thought and make a lot of sense to me.

Some more food for thought:
If you take two very well designed D/A converters, one 44.1K, the other 192K, the THD of the 192K converter will be FAR lower than the 44.1K converter at the high end of the audio spectrum. It is physically impossible for a 44.1K converter to accurately represent a complex waveform at these frequencies. There are simply not enough samples.
However, whether the human ear can respond quickly enough at these frequencies to accurately mirror a complex waveform anyway is something to consider. Especially given that the vast majority of people can't hear even a simple sinewave at 18KHz. This would make the THD issue at these frequencies almost redundant from a listening perspective and supports your views, Park. And, this is all comparing 44.1K to 192K. So I seriously doubt that any audible difference between 44.1K and 48K is going to be due exclusively to the difference in sample rate.

Personally, if my session is primarily for digital video or DVD, I use 48K and for CD, I use 44.1K and nearly always 24 bit.
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  #13  
Old 02-10-2002, 06:15 PM
where02190 where02190 is offline
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Default Re: sample rates...44.1 or 48...what do you use?

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:<HR>Originally posted by Doc:
Park,
My understanding of Nyquest is the same.
Perhaps my last post was a little misleading. Something I should add is that a complex waveform at the high end of the audio spectrum will actually contain harmonics outside the audio (assuming 20Hz-20KHz) spectrum.

What I was implying is that the 192KHz system will more accurately reproduce the complexities of this waveform but the human ear most likely won't hear the difference if it can't reproduce the harmonics that create the complex waveform. It will hear the same thing that the 44.1K system can reproduce.
In fact the 44.1K system is most likely to be more accurate in this area than a human ear (Unless you can hear above 22.05KHz).
<HR></BLOCKQUOTE>

Then why the push for 192k?
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  #14  
Old 02-11-2002, 07:11 AM
phamtec phamtec is offline
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Default Re: sample rates...44.1 or 48...what do you use?

You guys only ever talk (or think I guess) about tracking.

Once your stuff is in, there is a huge benefit to using high resolution data when mixing and adding effects.

It's seems pretty obvious to me that taking two 192k samples and combining with EQ and reverb at 192k is going to sound better than doing all of the same at 44k. It's pretty simple mathematics here (not rocket science).

And that's the point of high sample rate. Nothing to do with tracking.
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  #15  
Old 02-11-2002, 07:39 AM
Jason from MaggieJack Jason from MaggieJack is offline
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Default Re: sample rates...44.1 or 48...what do you use?

Haven't there been commercial albums that were done on adats at 16bit 44.1?
I thought most mikes and speaker systems only go from 20hz to 20khz at the most anyway, what would be the benefit then of the higher sample rates?

Jason
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  #16  
Old 02-11-2002, 09:00 AM
where02190 where02190 is offline
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Default Re: sample rates...44.1 or 48...what do you use?

For us old school analog guys think of it this way:

Bit depth=tape width
Sample rate=tape speed

We all know wider tape and faster speed means better fidelity, right?
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  #17  
Old 02-11-2002, 03:40 PM
dreeam dreeam is offline
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Default Re: sample rates...44.1 or 48...what do you use?

good call phamtec i second that!
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  #18  
Old 02-11-2002, 03:49 PM
Zeek Zeek is offline
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Default Re: sample rates...44.1 or 48...what do you use?

if the end porduct in 44.1 and you cannot afford professional mastering, 48k isn't worth your time, if CD or an MP3 is your final product.

If you are doing film work, then do 48k.

-zeek
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  #19  
Old 02-11-2002, 03:54 PM
Zeek Zeek is offline
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Default Re: sample rates...44.1 or 48...what do you use?

Also, the difference at a higher SR, such as 96k, is not the fact that you can hear stuff at higher Frequencies, for example, the nyquist for 96k is 48k and I don't think Dogs can even hear this, but more samples per second yields a much smother wave form in the digital domain to reflect what it would be in the Analog domain. Remember, Digital is not a smooth round waveform, they are jagged steps. The higher the SR, the smother the translation of the waveform in the digital domain.

If I'm wrong, nevermind me please [img]images/icons/grin.gif[/img]
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  #20  
Old 02-11-2002, 04:47 PM
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Park Seward Park Seward is offline
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Default Re: sample rates...44.1 or 48...what do you use?

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:<HR>Originally posted by Zeek:
but more samples per second yields a much smother wave form in the digital domain to reflect what it would be in the Analog domain. Remember, Digital is not a smooth round waveform, they are jagged steps. The higher the SR, the smother the translation of the waveform in the digital domain.

If I'm wrong, nevermind me please [img]images/icons/grin.gif[/img]
<HR></BLOCKQUOTE>

You are wrong. From a post Nike helped me with:


posted January 22, 2002 08:18 PM *** **** ** ** **
------------------------------------------------------------------------
[QUOTE]Originally posted by Park Seward:
Nika,

Please see if I understand all of this. Make any corrections as necessary.

The Nyquist theorem states that a sampling rate double of the audio frequency will properly define a waveform that is half of the sampling rate. That is, a sampling rate of 40k will properly define an audio frequency of 20k and below (not counting any low pass filters).

Minor correction: The Nyquist theorem states that a sampling rate more than double the highest frequency desired to be sampled will properly define a wavefom that is less than half of the sampling rate.

Increasing the 40k sampling rate will not further define the frequencies under 20k. They are already fully defined and can be faithfully reconstructed to analog.

In a perfect world this is the case. In an imperfect world we have to deal with the effects of the filters used to prevent aliasing. The concept of what you're saying is correct, so long as there are "perfect" filters in place.

Increasing the sampling rate will extend the frequency that can be defined in the digital realm.

Yes. It will also allow for "imperfect" or "less perfect" filters to be used because those will end up entirely above the audible spectrum. Once again, your point is correct, I'm just trying to add the necessary details to apply this information to the real world of converters.

Increasing the bit rate will increase the signal to noise ratio of the conversion but will not better define the audio within a given dynamic range. The increased bits are used to extend the dynamic range. Within a dynamic range of, say 50 db, a 16 bit signal and a 24 bit signal will sound the same.

Correct, so long as the signal is recorded hot enough to be fully captured.

The quality of the A/D and D/A converter and the stability of the clock will determine the quality of the sound more than just the sampling rate or the bit depth.

Increasing the bit depth and sample rate is a great bandaid for bad converters, as either of those improvements are a cheap way to get bad converters to sound good. But improving the analog section, clocking, filtering, and linearity of the conversion process itself is a less costly solution.

For those who have converters with poor filtering, sampling at higher frequencies MAY help, but buying new converters that are better will provide an equal, and possibly better result, as better converters will also generally fix a lot of the other issues that may be a problem in the converters besides just the quality of the filters.

I don't want to say that higher sampling WON'T or CAN'T make a difference, but the better the system is, the less viable those solutions are. Further, the differences in sampling frequency in ANY system are going to be pretty small, as the only change will be the filter. Changing the converters will provide a potentially large benefit as the analog section, clocking, and other aspects of the jitter will ALSO be improved, along with the filters.

If it's my money I buy new converters.

One week ago it was my money........I bought new converters.
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