[[email protected]]

I understand that I can get white noise by amplifying the noise of a Zenor diode
at it's "knee" point...

Is this a good quality white noise?

How can I filter it into pink noise?

Thanks!

[Audio1]

wrote:
I understand that I can get white noise by amplifying the noise of a Zenor diode
at it's "knee" point...

Is this a good quality white noise?

It's OK, you'll want to buffer the Zener with an amp stage or two,
http://www.maxim-ic.com/app-notes/index.mvp/id/3469

How can I filter it into pink noise?

-3dB/octave,
http://sound.westhost.com/project11.htm

I have a Heathkit AD-1309 noise generator, both white and pink with a
level control.

[Geoff]

Audio1 wrote:
wrote:
I understand that I can get white noise by amplifying the noise of a
Zenor diode at it's "knee" point...

Is this a good quality white noise?

It's OK, you'll want to buffer the Zener with an amp stage or two,
http://www.maxim-ic.com/app-notes/index.mvp/id/3469

How can I filter it into pink noise?

-3dB/octave,
http://sound.westhost.com/project11.htm

I have a Heathkit AD-1309 noise generator, both white and pink with a
level control.

Easiest to downlaoid a WAV and make a CD of it.

geoff

[John O'Flaherty]

On Thu, 18 Feb 2010 15:33:37 +1300, "geoff"
wrote:

Audio1 wrote:
wrote:
I understand that I can get white noise by amplifying the noise of a
Zenor diode at it's "knee" point...

Is this a good quality white noise?

It's OK, you'll want to buffer the Zener with an amp stage or two,
http://www.maxim-ic.com/app-notes/index.mvp/id/3469

How can I filter it into pink noise?

-3dB/octave,
http://sound.westhost.com/project11.htm

I have a Heathkit AD-1309 noise generator, both white and pink with a
level control.

Easiest to downlaoid a WAV and make a CD of it.

Or play it right out of the computer sound card as a signal generator.
--
John

[Arny Krueger]

wrote in message


I understand that I can get white noise by amplifying the
noise of a Zener diode at it's "knee" point...

If you really want to go for retro technology, why not use a vacuum tube
noise generator. I think it was some kind of a diode.

For the past 40 years, anybody who was serious about generating a noise
signal for audio did it digitally. The basic technology involves a clocked
shift register, if memory serves. Dedicated chips with this purpose were
once hot items for serious auido experimenters.

Is this a good quality white noise?

Back in the day I experimented with analog noise generators, and long story
short, I quickly shifted to digital approaches.

Today, you either generate the noise with software you already have (DAW) or
download a .wav file of the noise of your choice from the web. I think
Goldwave (shareware/freeware) generates pink, white, and red or brown
noise.

How can I filter it into pink noise?

In the day, we used analog pinking filters schematics of which are probably
still rattling around the web.

[Scott Dorsey]

wrote:
I understand that I can get white noise by amplifying the noise of a Zenor diode
at it's "knee" point...

Is this a good quality white noise?

Depends what you mean by good quality. It's very random. The distribution
is pretty white. It goes pretty far into the RF range.

How can I filter it into pink noise?

1/f integrator stage. Here's an example:
http://sound.westhost.com/project11.htm
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Ethan Winer[_3_]]

Here's mine:

http://www.ethanwiner.com/spectrum.html

The digital circuit in Figure 2 creates a very pure white noise, which
is then filtered to pink. Here's a 14-second Wave file that can be
looped seamlessly to any length:

http://www.ethanwiner.com/misc-conten/pinknoise.wav

--Ethan

[Ethan Winer[_3_]]

Oops, this link works:
http://www.ethanwiner.com/misc-content/pinknoise.wav

[GregS[_3_]]

In article , Ethan Winer wrote:
Oops, this link works:
http://www.ethanwiner.com/misc-content/pinknoise.wav

A circuit probably similar to the one Old Colony sold.
One neat trick was it could be set to stereo or mono.

greg

[[email protected]]

On Thu, 18 Feb 2010 08:08:45 -0500, "Arny Krueger" wrote:

wrote in message


I understand that I can get white noise by amplifying the
noise of a Zener diode at it's "knee" point...

If you really want to go for retro technology, why not use a vacuum tube
noise generator. I think it was some kind of a diode.

Really? You must be channeling Edison... A vacuum tube is not a solid state
zenor, which is known as a reliable noise generator. Perhaps you could Google it
and read up on that...

For the past 40 years, anybody who was serious about generating a noise
signal for audio did it digitally. The basic technology involves a clocked
shift register, if memory serves. Dedicated chips with this purpose were
once hot items for serious auido experimenters.

You are implying that I am not serious?

I know about digital noise generators, (pseudo random sequencers), they are a
lot more complicated than a zenor, resistor, and cap...

Is this a good quality white noise?

Back in the day I experimented with analog noise generators, and long story
short, I quickly shifted to digital approaches.

Today, you either generate the noise with software you already have (DAW) or
download a .wav file of the noise of your choice from the web. I think
Goldwave (shareware/freeware) generates pink, white, and red or brown
noise.

Actually that's probably the best way, I'll make a CDR.

How can I filter it into pink noise?

In the day, we used analog pinking filters schematics of which are probably
still rattling around the web.


Pinking filter eh? Sounds distinctly communist!

[Don Pearce[_3_]]

On Thu, 18 Feb 2010 15:58:40 -0500, wrote:

If you really want to go for retro technology, why not use a vacuum tube
noise generator. I think it was some kind of a diode.

Really? You must be channeling Edison... A vacuum tube is not a solid state
zenor, which is known as a reliable noise generator. Perhaps you could Google it
and read up on that...

Dunno about a vacuum tube noise generator, but a neon tube does the
job very well.

d

[Arny Krueger]

"Don Pearce" wrote in message

On Thu, 18 Feb 2010 15:58:40 -0500, wrote:

If you really want to go for retro technology, why not
use a vacuum tube noise generator. I think it was some
kind of a diode.

Really? You must be channeling Edison... A vacuum tube
is not a solid state zenor, which is known as a reliable
noise generator. Perhaps you could Google it and read up
on that...

Dunno about a vacuum tube noise generator, but a neon
tube does the job very well.

http://mysite.du.edu/~etuttle/electr...ct27.htm#Noise

"
The Noise Diode
A special kind of diode should be mentioned here, because experiments with
it are quite interesting. It is the noise diode, intended for the specific
purpose of producing wide-band RF noise through the shot effect. Shot effect
noise is fluctuations in the anode current due to the random collection of
electrons. We have already mentioned that the anode current is controlled by
the space charge around the filament. It was discovered, to some surprise,
that this correlated successive electrons so that they were emitted
regularly to maintain a constant current, and therefore the shot effect was
nearly completely eliminated. That is, a normal diode has no shot effect
noise in its plate current.

The noise diode is designed so that at reasonable plate voltages, all
electrons emitted by the filament are immediately drawn to the plate without
forming much of a space charge. Since the electrons are emitted randomly,
the anode current will show the full shot effect noise. This is done by
purposely making the filament to have low emission. To do this, a tungsten
filament is used. Noise diodes give us the opportunity to observe a tungsten
filament, as well as temperature saturation.

An available noise diode is the 5722, whose basing is shown at the right.
The 7-pin miniature tube was made as late as 1977, and now costs about $14,
which is probably not much more than when it was new. The maximum plate
voltage is given as 200 V, and the maximum plate current as 35 mA, so
apparently the plate can dissipate 7 W. The plate has wings that make a good
dissipation probable.
"

My recollection is that while the primary purpose of this device was the
production of RF noise, its output in the audio band was sometimes used,
back in the days of tubes.

[Arny Krueger]

wrote in message

On Thu, 18 Feb 2010 08:08:45 -0500, "Arny Krueger"
wrote:

wrote in message


I understand that I can get white noise by amplifying
the noise of a Zener diode at it's "knee" point...

If you really want to go for retro technology, why not
use a vacuum tube noise generator. I think it was some
kind of a diode.

Really? You must be channeling Edison... A vacuum tube is
not a solid state zenor, which is known as a reliable
noise generator. Perhaps you could Google it and read up
on that...

For the past 40 years, anybody who was serious about
generating a noise signal for audio did it digitally.
The basic technology involves a clocked shift register,
if memory serves. Dedicated chips with this purpose were
once hot items for serious auido experimenters.

You are implying that I am not serious?

You are the best judge of that.

I know about digital noise generators, (pseudo random
sequencers), they are a lot more complicated than a
zenor, resistor, and cap...

The above 3 parts were replaced by 1 chip with 4 terminal connections:

http://www.datasheetcatalog.org/data.../455558_DS.pdf

Is this a good quality white noise?

Back in the day I experimented with analog noise
generators, and long story short, I quickly shifted to
digital approaches.

What I'm saying is that I tried the zener noise source approach, and quickly
moved on.

Today, you either generate the noise with software you
already have (DAW) or download a .wav file of the noise
of your choice from the web. I think Goldwave
(shareware/freeware) generates pink, white, and red or
brown noise.

Actually that's probably the best way, I'll make a CDR.

There you go! Good move.

How can I filter it into pink noise?

In the day, we used analog pinking filters schematics of
which are probably still rattling around the web.

Pinking filter eh? Sounds distinctly communist!

During the Cold War we used the phrase with nary a tinge:

http://www.firstpr.com.au/dsp/pink-noise/

[Scott Dorsey]

In article ,
On Thu, 18 Feb 2010 08:08:45 -0500, "Arny Krueger" wrote:

wrote in message
m

I understand that I can get white noise by amplifying the
noise of a Zener diode at it's "knee" point...

If you really want to go for retro technology, why not use a vacuum tube
noise generator. I think it was some kind of a diode.

Really? You must be channeling Edison... A vacuum tube is not a solid state
zenor, which is known as a reliable noise generator. Perhaps you could Google it
and read up on that...

No, he's talking about a noise tube. It's some sort of goofy diode that
is placed in an external magnetic field. The GenRad noise sources and
noise bridges used them. I don't think they have any actual advantage over
a zener other than looking cool.
--scott


--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Arny Krueger]

"Scott Dorsey" wrote in message

In article ,
On Thu, 18 Feb 2010 08:08:45 -0500, "Arny Krueger"
wrote:

wrote in message


I understand that I can get white noise by amplifying
the noise of a Zener diode at it's "knee" point...

If you really want to go for retro technology, why not
use a vacuum tube noise generator. I think it was some
kind of a diode.

Really? You must be channeling Edison... A vacuum tube
is not a solid state zenor, which is known as a reliable
noise generator. Perhaps you could Google it and read up
on that...

No, he's talking about a noise tube. It's some sort of
goofy diode that is placed in an external magnetic field.
The GenRad noise sources and noise bridges used them. I
don't think they have any actual advantage over a zener
other than looking cool. --scott

AFAIK the major advantage of noise diode tubes over zeners is that the tubes
rather significantly pre-existed the zeners. ;-)

[[email protected]]

On Thu, 18 Feb 2010 17:03:27 -0500, "Arny Krueger" wrote:

wrote in message

On Thu, 18 Feb 2010 08:08:45 -0500, "Arny Krueger"
wrote:

wrote in message


I understand that I can get white noise by amplifying
the noise of a Zener diode at it's "knee" point...

If you really want to go for retro technology, why not
use a vacuum tube noise generator. I think it was some
kind of a diode.

Really? You must be channeling Edison... A vacuum tube is
not a solid state zenor, which is known as a reliable
noise generator. Perhaps you could Google it and read up
on that...

For the past 40 years, anybody who was serious about
generating a noise signal for audio did it digitally.
The basic technology involves a clocked shift register,
if memory serves. Dedicated chips with this purpose were
once hot items for serious auido experimenters.

You are implying that I am not serious?

You are the best judge of that.

I know about digital noise generators, (pseudo random
sequencers), they are a lot more complicated than a
zenor, resistor, and cap...

The above 3 parts were replaced by 1 chip with 4 terminal connections:

http://www.datasheetcatalog.org/data.../455558_DS.pdf

Actually, thats a white noise gen, and would require a pinking filter...

Is this a good quality white noise?

Back in the day I experimented with analog noise
generators, and long story short, I quickly shifted to
digital approaches.

What I'm saying is that I tried the zener noise source approach, and quickly
moved on.

Today, you either generate the noise with software you
already have (DAW) or download a .wav file of the noise
of your choice from the web. I think Goldwave
(shareware/freeware) generates pink, white, and red or
brown noise.

Actually that's probably the best way, I'll make a CDR.

I never looked before, but my sound editor has a pink noise sim... I should open
my eyes, eh?

There you go! Good move.

How can I filter it into pink noise?

In the day, we used analog pinking filters schematics of
which are probably still rattling around the web.

Pinking filter eh? Sounds distinctly communist!

During the Cold War we used the phrase with nary a tinge:

http://www.firstpr.com.au/dsp/pink-noise/

[[email protected]]

On Thu, 18 Feb 2010 18:41:08 -0500, "Arny Krueger" wrote:

"Scott Dorsey" wrote in message

In article ,
On Thu, 18 Feb 2010 08:08:45 -0500, "Arny Krueger"
wrote:

wrote in message


I understand that I can get white noise by amplifying
the noise of a Zener diode at it's "knee" point...

If you really want to go for retro technology, why not
use a vacuum tube noise generator. I think it was some
kind of a diode.

Really? You must be channeling Edison... A vacuum tube
is not a solid state zenor, which is known as a reliable
noise generator. Perhaps you could Google it and read up
on that...

No, he's talking about a noise tube. It's some sort of
goofy diode that is placed in an external magnetic field.
The GenRad noise sources and noise bridges used them. I
don't think they have any actual advantage over a zener
other than looking cool. --scott

AFAIK the major advantage of noise diode tubes over zeners is that the tubes
rather significantly pre-existed the zeners. ;-)

Pre-dating is not an advantage... especially with a wasteful tube! Small and
cold is why technology marches forward!

In practical terms, I have a box of various zeners and weirdo diodes... some
exhibiting reverse resistance and such anomalies... but the only tubes I have
are guitar amp types, and probably a box of old TV tubes in the basement... no
noise diode tubes... Imagine the hassle of setting one of those up!

But computer sims seem to be the best bet!

[chris-]

How can I filter it into pink noise?

See http://en.wikipedia.org/wiki/Colors_of_noise for details of how to
filter white to pink noise.

Chris-
http://multitrackmixers.com/
http://djsetup.net/

[Scott Dorsey]

wrote:
In practical terms, I have a box of various zeners and weirdo diodes... some
exhibiting reverse resistance and such anomalies... but the only tubes I have
are guitar amp types, and probably a box of old TV tubes in the basement... no
noise diode tubes... Imagine the hassle of setting one of those up!

It's not so bad, I just had a Gen-Rad on the bench not too long ago. But
you could readily use any gas-filled tube, I think. Even a cold cathode
backlight from a laptop....
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[david gourley]

(Scott Dorsey) put forth the notion in...news:hlkirc$ejp$1
@panix2.panix.com:

In article ,
On Thu, 18 Feb 2010 08:08:45 -0500, "Arny Krueger"
wrote:

wrote in message
om

I understand that I can get white noise by amplifying the
noise of a Zener diode at it's "knee" point...

If you really want to go for retro technology, why not use a vacuum tube
noise generator. I think it was some kind of a diode.

Really? You must be channeling Edison... A vacuum tube is not a solid
state
zenor, which is known as a reliable noise generator. Perhaps you could
Google it
and read up on that...

No, he's talking about a noise tube. It's some sort of goofy diode that
is placed in an external magnetic field. The GenRad noise sources and
noise bridges used them. I don't think they have any actual advantage
over
a zener other than looking cool.
--scott



I have a GSC 901B Noise Gen that uses a 6D4 between a couple of magnets in
that fashion.

david

[[email protected]]

David
Would you be willing to sell your gsc 901b ?
Thanks

[[email protected]]

I wonder if he wants the quote in 2010 dollars or 2015?
Mark