SAE fun

[Rudi Gerberich]

http://www.saecollege.de/reference_material/pages/Recorders.htm

read "Sampling Rate" - enjoy;-)

[Don Pearce]

On Fri, 26 Jan 2007 23:24:18 +0100, "Rudi Gerberich" >
wrote:

>http://www.saecollege.de/reference_material/pages/Recorders.htm
>
>read "Sampling Rate" - enjoy;-)
>

I understood sampling theory ten minutes ago. I don't any more.

d

--
Pearce Consulting
http://www.pearce.uk.com

--
Posted via a free Usenet account from http://www.teranews.com

[Carey Carlan]

(Don Pearce) wrote in news:45ba81c4.304743125
@free.teranews.com:

> On Fri, 26 Jan 2007 23:24:18 +0100, "Rudi Gerberich" >
> wrote:
>
>>http://www.saecollege.de/reference_material/pages/Recorders.htm
>>read "Sampling Rate" - enjoy;-)
>
> I understood sampling theory ten minutes ago. I don't any more.

I understand it just fine. These couple of paragraphs are nonsense.

[Don Pearce]

On Fri, 26 Jan 2007 22:41:54 GMT, Carey Carlan >
wrote:

(Don Pearce) wrote in news:45ba81c4.304743125
:
>
>> On Fri, 26 Jan 2007 23:24:18 +0100, "Rudi Gerberich" >
>> wrote:
>>
>>>http://www.saecollege.de/reference_material/pages/Recorders.htm
>>>read "Sampling Rate" - enjoy;-)
>>
>> I understood sampling theory ten minutes ago. I don't any more.
>
>I understand it just fine. These couple of paragraphs are nonsense.

That was indeed the essence of my joke.

d

--
Pearce Consulting
http://www.pearce.uk.com

--
Posted via a free Usenet account from http://www.teranews.com

[Daniel Fuchs]

Rudi Gerberich wrote:
>
> http://www.saecollege.de/reference_material/pages/Recorders.htm
>
> read "Sampling Rate" - enjoy;-)

"Did you know that when an ADat or D88 records on a new track
it plays the bit stream off the tape , mixes in the new track, and
records
it again. Now that's worth thinking about"

Really... Now I've really got somethink to think about...


Daniel

[Mike Rivers]

Daniel Fuchs wrote:

> "Did you know that when an ADat or D88 records on a new track
> it plays the bit stream off the tape , mixes in the new track, and
> records
> it again. Now that's worth thinking about"

I don't think that's true with the ADAT, but since the DA88 treats
tracks as pairs (or a stereo track, if you prefer), if you have Track 3
recorded and then record Track 4, when you recorded Track 3, you
actually recorded Tracks 3 and 4 - whatever audio you sent to Track 3
and silence on Track 4. Then when you recorded Track 4, Track 3's audio
was re-recorded together with the new audio for Track 4.

Alesis boosters used this as a bit of mud slinging (remember, the ADAT
came out first but most thought the DA-88 sounded better and had some
other advantages) saying that every time you recorded a new track you
risked losing a previously recorded track if something failed. In
reality, it never happened. You could pull the power plug when
recording a new track and all the previous tracks were intact. Very
clever, those Japanese.

What this has to do with sample rate, I dunno. I didn't read the SAE
reference.

[Roy W. Rising]

"Rudi Gerberich" > wrote:
> http://www.saecollege.de/reference_material/pages/Recorders.htm
>
> read "Sampling Rate" - enjoy;-)

Intellectually, I know that using a 44.1 KHz sampling rate there should be
some kind of anomally when a sine wave of 11.025 KHz (44.1 / 4) is
recorded. After all, there are so few samples per cycle from which to
reconstruct the waveform! But ... I've done the test ... A/D~D/A @ 44.1
KHz. As my sine wave generator sweeps upward from 10 KHz, the
ocilloscope's waveform display stays smoothly sinusoidal. At 11.025 KHz,
nothing changes! As Carson would say "How dey do dat?" Somewhere in the
darkness Ron Extes whispers "algorithms!"

--
~ Roy
"It's NOT the mic, it's NOT the preamp!"

[Scott Dorsey]

Roy W. Rising > wrote:
>
>Intellectually, I know that using a 44.1 KHz sampling rate there should be
>some kind of anomally when a sine wave of 11.025 KHz (44.1 / 4) is
>recorded. After all, there are so few samples per cycle from which to
>reconstruct the waveform!

There are PLENTY. It takes two samples to reconstruct a sine wave, and of
course everything is really the sum of sines. Those two statements are
the base on which the Sampling Theorem is based.

There is a good intuitive discussion of this in the FAQ.

But ... I've done the test ... A/D~D/A @ 44.1
>KHz. As my sine wave generator sweeps upward from 10 KHz, the
>ocilloscope's waveform display stays smoothly sinusoidal. At 11.025 KHz,
>nothing changes! As Carson would say "How dey do dat?" Somewhere in the
>darkness Ron Extes whispers "algorithms!"

No, not at all. It takes two samples, and you know everything about a sine
wave. It takes two samples per cycle of the highest frequency in a bandlimited
waveform, and you know everything about it.

It seems confusing at first, but JJ's explanation is good... and when you
get an intuitive idea of how it works, it's just plain neat.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Jay-atldigi]

In article >,
(Don Pearce) wrote:

> On Fri, 26 Jan 2007 23:24:18 +0100, "Rudi Gerberich" >
> wrote:
>
> >http://www.saecollege.de/reference_material/pages/Recorders.htm
> >read "Sampling Rate" - enjoy;-)
>
> I understood sampling theory ten minutes ago. I don't any more.
>
> d

That link contains what may be the worst bunch of crap I've ever seen.
Never mind the lack of clarity in the writing, but it's just not
accurate.

If this is what they're teaching their students, no wonder professional
audio is suffering. How do they let that stuff through? Isn't anybody
paying attention? If the author was actually correct about sampling, and
had managed to prove Nyquist and Shannon wrong, I imagine he would have
gotten an invitation to a dinner from those nice people at Nobel, and we
all would have heard about it. Sheesh. How depressing.

--
Jay Frigoletto
Mastersuite
www.promastering.com

[Les Cargill]

Roy W. Rising wrote:

> "Rudi Gerberich" > wrote:
>
>>http://www.saecollege.de/reference_material/pages/Recorders.htm
>>
>>read "Sampling Rate" - enjoy;-)
>
>
> Intellectually, I know that using a 44.1 KHz sampling rate there should be
> some kind of anomally when a sine wave of 11.025 KHz (44.1 / 4) is
> recorded. After all, there are so few samples per cycle from which to
> reconstruct the waveform! But ... I've done the test ... A/D~D/A @ 44.1
> KHz. As my sine wave generator sweeps upward from 10 KHz, the
> ocilloscope's waveform display stays smoothly sinusoidal. At 11.025 KHz,
> nothing changes! As Carson would say "How dey do dat?" Somewhere in the
> darkness Ron Extes whispers "algorithms!"
>

There is no pole, Neo.

May the spirit of Nyquist shine upon you.

--
Les Cargill

[Bob Cain]

Scott Dorsey wrote:
> Roy W. Rising > wrote:
>> Intellectually, I know that using a 44.1 KHz sampling rate there should be
>> some kind of anomally when a sine wave of 11.025 KHz (44.1 / 4) is
>> recorded. After all, there are so few samples per cycle from which to
>> reconstruct the waveform!
>
> There are PLENTY. It takes two samples to reconstruct a sine wave, and of
> course everything is really the sum of sines. Those two statements are
> the base on which the Sampling Theorem is based.
>
> There is a good intuitive discussion of this in the FAQ.
>
> But ... I've done the test ... A/D~D/A @ 44.1
>> KHz. As my sine wave generator sweeps upward from 10 KHz, the
>> ocilloscope's waveform display stays smoothly sinusoidal. At 11.025 KHz,
>> nothing changes! As Carson would say "How dey do dat?" Somewhere in the
>> darkness Ron Extes whispers "algorithms!"
>
> No, not at all. It takes two samples, and you know everything about a sine
> wave.

Huh?


Bob
--

"Things should be described as simply as possible, but no simpler."

A. Einstein

[Don Pearce]

On Fri, 26 Jan 2007 20:14:03 -0800, Bob Cain
> wrote:

>Scott Dorsey wrote:
>> Roy W. Rising > wrote:
>>> Intellectually, I know that using a 44.1 KHz sampling rate there should be
>>> some kind of anomally when a sine wave of 11.025 KHz (44.1 / 4) is
>>> recorded. After all, there are so few samples per cycle from which to
>>> reconstruct the waveform!
>>
>> There are PLENTY. It takes two samples to reconstruct a sine wave, and of
>> course everything is really the sum of sines. Those two statements are
>> the base on which the Sampling Theorem is based.
>>
>> There is a good intuitive discussion of this in the FAQ.
>>
>> But ... I've done the test ... A/D~D/A @ 44.1
>>> KHz. As my sine wave generator sweeps upward from 10 KHz, the
>>> ocilloscope's waveform display stays smoothly sinusoidal. At 11.025 KHz,
>>> nothing changes! As Carson would say "How dey do dat?" Somewhere in the
>>> darkness Ron Extes whispers "algorithms!"
>>
>> No, not at all. It takes two samples, and you know everything about a sine
>> wave.
>
>Huh?

Quite. It takes MORE than two samples to know everything about at sine
wave. 2.00000001 will do, 2.0000000 will not.

d

--
Pearce Consulting
http://www.pearce.uk.com

--
Posted via a free Usenet account from http://www.teranews.com

[Ben Bradley]

4On Fri, 26 Jan 2007 23:58:28 +0100, Daniel Fuchs
> wrote:

>
>
>Rudi Gerberich wrote:
>>
>> http://www.saecollege.de/reference_material/pages/Recorders.htm
>>
>> read "Sampling Rate" - enjoy;-)

I've read this type of thing before from various posters here and
there, but please - I was enjoying a good dinner until I read through
it. I'm just glad he didn't quote me as part of that article, not that
I'm famous or quotable or anything...

>
>"Did you know that when an ADat or D88 records on a new track
>it plays the bit stream off the tape , mixes in the new track, and
>records
>it again. Now that's worth thinking about"
>
>Really... Now I've really got somethink to think about...

Perhaps you should check this out:

http://raft.wash.org/thinkers.html

The author of that article may already be a long-term member. He
says something is "worth thinking about" but then he goes off into the
next section.

>
>
>Daniel