I'm always curious about my source material bandwidth. "This CD sound
really thin, is there any bass at all? Is the bass too low in level or
there a cut-off somewhere?" and "Jeez, this old recording is really
not eligible, is there something at all over 5 KHz?"

This type of questions would be very easy to answer if I just had the
right tool. Is there such a tool I could use in a Windows PC?

Per Stromgren wrote:
I'm always curious about my source material bandwidth.
This CD sound really thin, is there any bass at all? Is the
bass too low in level or there a cut-off somewhere?"
and "Jeez, this old recording is really not eligible, is there
something at all over 5 kHz?"
This type of questions would be very easy to answer if
I just had the right tool. Is there such a tool I could use
in a Windows PC?


Your Google word is
frequency analyzer

Cheers

ebs

On Fri, 26 Nov 2004 22:46:12 +0100, "Eberhard Sengpiel"
wrote:

Per Stromgren wrote:
I'm always curious about my source material bandwidth.
This CD sound really thin, is there any bass at all? Is the
bass too low in level or there a cut-off somewhere?"
and "Jeez, this old recording is really not eligible, is there
something at all over 5 kHz?"
This type of questions would be very easy to answer if
I just had the right tool. Is there such a tool I could use
in a Windows PC?


Your Google word is
frequency analyzer

Thatks, I have tried a few cheap (i.e. free) ones, but all of them
report 20 Hz content from a big band sample (Doug Sax recording of
Harry James in Corner Pocket). There is no instrument that can play
20Hz in that band! Low E on the upright bass is 43 Hz if I am not
mistaken.

Per.

"Per Stromgren" wrote ...
Thatks, I have tried a few cheap (i.e. free) ones, but all of them
report 20 Hz content from a big band sample (Doug Sax recording of
Harry James in Corner Pocket). There is no instrument that can play
20Hz in that band! Low E on the upright bass is 43 Hz if I am not
mistaken.

But the traffic out on the street likely does 20Hz without even trying.
Wasn't that recorded in a church down the street with long lines
running back to the Sheffield studio?

Of course, if you have the original black vinyl, 20Hz could also be
attributable to turntable rumble or any of the other abundant artifacts
of the medium.

On Sat, 27 Nov 2004 05:30:30 -0800, "Richard Crowley"
wrote:

"Per Stromgren" wrote ...
Thatks, I have tried a few cheap (i.e. free) ones, but all of them
report 20 Hz content from a big band sample (Doug Sax recording of
Harry James in Corner Pocket). There is no instrument that can play
20Hz in that band! Low E on the upright bass is 43 Hz if I am not
mistaken.

But the traffic out on the street likely does 20Hz without even trying.
Wasn't that recorded in a church down the street with long lines
running back to the Sheffield studio?

Yes, that rings a bell. (!) But I don't think that is what I see. My
Stax Lambdas should be able to reproduce 20 Hz easily, and I don't
hear it through them.


Of course, if you have the original black vinyl, 20Hz could also be
attributable to turntable rumble or any of the other abundant artifacts
of the medium.

This was the CD realease.

I think this some other effect, as it this is what I get from morre or
less any recording, except a 1kHz tone. Is this perhaps some artifact
of FFT in a too small time window, or some such?

(I should know this, but my memory is aging, I'm afraid. Perhaps this
is the time to read up on FFT.)

Thanks, Richard.

Per.

Per,

My Stax Lambdas should be able to reproduce 20 Hz easily, and I don't hear
it through them.

20 Hz is probably too low to hear. Yeah, I know everyone says the range of
human hearing is from 20 Hz to 20 KHz. But most people can't hear to 20 KHz
either. Not long ago I tested this myself using a subwoofer that plays to 18
Hz (maybe even lower) and I couldn't perceive it as a tone until the
frequency got up to 25 Hz. Yes, I tested loudly! With my hand on the speaker
cone I saw and felt no difference between 20, 22, and 25 Hz, and I could
easily hear the rush of air at all three frequencies too. But it wasn't
audible as a pitch to me below 25 Hz.

If you're playing with a spectrum analyzer program and unsure of the
results, try feeding it known frequencies one at a time so you can verify
that what it shows is correct.

--Ethan

On Sat, 27 Nov 2004 10:43:03 +0100, Per Stromgren
wrote:

Thatks, I have tried a few cheap (i.e. free) ones, but all of them
report 20 Hz content from a big band sample (Doug Sax recording of
Harry James in Corner Pocket).

That's most likely an artefact of your frequency analyzer.
To detect 20 Hz you need long sample sizes. You may as well
play with different windowing functions. Try a FFT size of
65536 samples and Blackman-Harris as windowing function.

The program doesn't offer these settings? Get a better one.

HTH
Norbert

Per Stromgren wrote in
:

I'm always curious about my source material bandwidth. "This CD sound
really thin, is there any bass at all? Is the bass too low in level or
there a cut-off somewhere?" and "Jeez, this old recording is really
not eligible, is there something at all over 5 KHz?"

This type of questions would be very easy to answer if I just had the
right tool. Is there such a tool I could use in a Windows PC?


RealRTA or any RTA type software can tell you this.



--
Lucas Tam )
Please delete "REMOVE" from the e-mail address when replying.
http://members.ebay.com/aboutme/coolspot18/

You would need a spectrum analyser to properly do what you want.

--

Jerry G.
======


"Per Stromgren" wrote in message
...
I'm always curious about my source material bandwidth. "This CD sound
really thin, is there any bass at all? Is the bass too low in level or
there a cut-off somewhere?" and "Jeez, this old recording is really
not eligible, is there something at all over 5 KHz?"

This type of questions would be very easy to answer if I just had the
right tool. Is there such a tool I could use in a Windows PC?