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It would be nice if the exemplary sonograms were accompagnied by the corresponding sound files (.ogg) so that we could hear what we see :-) -- Dipoar ( talk) 01:06, 3 October 2008 (UTC)
I removed the parenthetical claim that AT used Coagula because this site that's in the links section says he used metasynth. If anyone has a really solid reference, we can put it back up. -- Hurtstotouchfire 02:45, 15 October 2007 (UTC)
the picture is still visible in the mp3, just not as clear. i just checked. Omegatron 06:35, Feb 1, 2004 (UTC)
If this image reappears, put it back in:
A sonogram of a male voice saying [tatata], as displayed by Praat.
The label for the "tatata" spectrogram should state the mother tongue of the speaker.
Could we have a reference for the Tubular Bells, Rugby Transmitter spectrogram?
I think it should read 24Hz instead of 24Khz, could someone more knowledgeable than me check this ? Zeno 04:02, 9 January 2007 (UTC)
Nevermind, i'm an audio guy, not a radio guy ! 24k is very low radio freq ! Zeno 04:08, 9 January 2007 (UTC)
I am suggesting that Waterfall plot be merged into the Spectrogram page. They are essentially the same thing and the terms are interchangable. A waterfall plot can be 2D with color being the third dimension. A spectrogram can also be a 3D display. The only issue is that the Waterfall Plot page has a focus on room acoustics while Spectrogram is more of DSP term. ( Spectrogram 05:51, 27 January 2007 (UTC))
While I agree that they carry the same information, I'm not sure they're the same. From my limited knowledge, a waterfall plot is merely a type of 3D plot that is often used to display freq. response vs. time. Check http://www.caspur.it/risorse/softappl/doc/matlab_help/techdoc/ref/waterfall.html for MATLAB's description which is a completely different description than what they have for spectrogram. Weston.pace 19:29, 5 July 2007 (UTC)
I have clarified the definition of waterfall plot and believe it is now contains enough unique content to no longer require a merge. Weston.pace 21:30, 5 July 2007 (UTC)
I added a image of a FM spectrogram. The 'edit' link below it was moved over and I was unsure how to move it back. stemperm 20:35, 13 February 2007 (UTC)
How do people feel about a section regarding how to read spectrograms for speech analysis? Subsection? Separate article? I'd be willing to contribute. -- Coyne025 17:17, 22 February 2007 (UTC)
The second line of this article is: "It is a three-dimensional plot of the energy of the frequency content of a signal as it changes over time." I don't know anything about a spectogram but I can only see two dimensions: 1) the energe of the frequency content of a signal and 2) time. Isn't two-dimensional more correct? Lova Falk ( talk) 16:10, 17 January 2008 (UTC)
From user Spectrum1234:
I say it is 3-D. Is very thin paper 2-D or 3-D (even when viewed on your 2-D monitor) ?
Look at these spectrum plots (90' and 60') from the Goldwave program of an extremely quiet noise burst (thus it is about as 2-D (flat) as it could be, yet) it still 'looks' like it is 3-D (to the extent possible on a 2-D monitor):
Someone should link this page to the italian corresponding article in italian, "Spettrogramma" —Preceding unsigned comment added by 151.67.178.125 ( talk) 11:42, 13 June 2009 (UTC)
Where sonograph redirects to this page, sonography redirects to medical ultrasonography. This does not seem consistent, should we change this? -- 130.89.139.73 ( talk) 13:26, 23 July 2009 (UTC)
These two voice spectrograms are awful, they use such a low frequency resolution that you cannot distinguish any of their sonorants, they appear all fused together, which is misleading, and doesn't show how the pitch of voice varies (doesn't show the pitch at all actually). -- 89.124.241.234 ( talk) 14:19, 13 November 2009 (UTC)
This edit added the following to the lead section: "In the field of time–frequency signal processing, it is one of the most popular quadratic Time-Frequency Distribution that represents a signal in a joint time-frequency domain and that has the property of being positive." Does that mean something to the regular contributors? Maybe there's just a simple typo throwing me off, but as a first-time visitor here, even with some experience with signal processing, I can't understand a word of it. For example, the terms "quadratic", "positive" and "distribution" are not defined, nor do they play much of a role in the article. Spiel496 ( talk) 17:44, 27 April 2011 (UTC)
They do not bear any apparent relation to the subject (spectrogram) or content of the article. Did some previous editor get confused between cryptograms and spectrograms? — Preceding unsigned comment added by 167.216.14.162 ( talk) 22:56, 15 September 2011 (UTC)
According to [3] a spectrogram is a "A graphic or photographic representation of a spectrum" - which is what I always understood the general term spectrogram means. For example you could have a spectrogram of the light observed from a star. This article gives the impression that a spectrogram is always related to sound waves. You can also find scientific papers ( [4]) citing the term spectrogram in relation to other spectra than just sound waves. 202.180.125.97 ( talk) 18:54, 2 October 2013 (UTC)
When you click this link under "External Links", it links to a page that doesn't exist. Can someone fix this maybe? 2601:8B:4400:C180:2048:CDF2:690E:727 ( talk) 01:33, 30 December 2015 (UTC)
Some recent edits have raised the issue again about how this Spectrogram article is restricted to sound while the Spectograph article seems more restricted to EM radiation. The sentence Kvng reverted is generally correct, albeit added without source. A spectogram is the output of a spectrograph, or someimtes the result of digital transformation of the input signal in a manner that is generally analogous to what a spectrograph does. Who wants to step up to resolve this? It requires an editor who can pull information from multiple disciplines. I'm happy to help, but don't think I can do the entire thing myself. —jmcgnh (talk) (contribs) 23:16, 22 August 2016 (UTC)
How would the resolution of a spectrogram obtained with a "series of band-pass filters" compare against that created conventionally via an FFT? Particularly in the low-mid audio frequency range. An FFT or a "digital" equalizer is quite poor at resolving narrow tones without compromising the time-resolution across the spectrum. I guess there must be a catch, because this type of filter isn't used anywhere. I would like to hear an explanation with minimal maths. J7n ( talk) 17:20, 11 February 2017 (UTC)
I am not aware of spectrograms that don't use time as one of their axis. Greglocock asserts that RPM can replace time and provides this citation. These plots have frequency, amplitude and RPM axis but there is no indication they're called or considered spectrograms. I have marked this with {{ fv}}. I think Greglocock would prefer if I just marked "or some other variable" in the lead with {{ cn}} but, like I said, I'm not aware of any spectrograms that don't use time and it is difficult to prove a negative. ~ Kvng ( talk) 15:34, 9 November 2017 (UTC)
![]() | This article is rated C-class on Wikipedia's
content assessment scale. It is of interest to the following WikiProjects: | |||||||||||||||||||||||||||||||||||||||||||||||||||||
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![]() | This talk page is for
discussion on how to improve the
Spectrogram article. If you would like to ask questions about the subject, please address them to the Reference desk. |
It would be nice if the exemplary sonograms were accompagnied by the corresponding sound files (.ogg) so that we could hear what we see :-) -- Dipoar ( talk) 01:06, 3 October 2008 (UTC)
I removed the parenthetical claim that AT used Coagula because this site that's in the links section says he used metasynth. If anyone has a really solid reference, we can put it back up. -- Hurtstotouchfire 02:45, 15 October 2007 (UTC)
the picture is still visible in the mp3, just not as clear. i just checked. Omegatron 06:35, Feb 1, 2004 (UTC)
If this image reappears, put it back in:
A sonogram of a male voice saying [tatata], as displayed by Praat.
The label for the "tatata" spectrogram should state the mother tongue of the speaker.
Could we have a reference for the Tubular Bells, Rugby Transmitter spectrogram?
I think it should read 24Hz instead of 24Khz, could someone more knowledgeable than me check this ? Zeno 04:02, 9 January 2007 (UTC)
Nevermind, i'm an audio guy, not a radio guy ! 24k is very low radio freq ! Zeno 04:08, 9 January 2007 (UTC)
I am suggesting that Waterfall plot be merged into the Spectrogram page. They are essentially the same thing and the terms are interchangable. A waterfall plot can be 2D with color being the third dimension. A spectrogram can also be a 3D display. The only issue is that the Waterfall Plot page has a focus on room acoustics while Spectrogram is more of DSP term. ( Spectrogram 05:51, 27 January 2007 (UTC))
While I agree that they carry the same information, I'm not sure they're the same. From my limited knowledge, a waterfall plot is merely a type of 3D plot that is often used to display freq. response vs. time. Check http://www.caspur.it/risorse/softappl/doc/matlab_help/techdoc/ref/waterfall.html for MATLAB's description which is a completely different description than what they have for spectrogram. Weston.pace 19:29, 5 July 2007 (UTC)
I have clarified the definition of waterfall plot and believe it is now contains enough unique content to no longer require a merge. Weston.pace 21:30, 5 July 2007 (UTC)
I added a image of a FM spectrogram. The 'edit' link below it was moved over and I was unsure how to move it back. stemperm 20:35, 13 February 2007 (UTC)
How do people feel about a section regarding how to read spectrograms for speech analysis? Subsection? Separate article? I'd be willing to contribute. -- Coyne025 17:17, 22 February 2007 (UTC)
The second line of this article is: "It is a three-dimensional plot of the energy of the frequency content of a signal as it changes over time." I don't know anything about a spectogram but I can only see two dimensions: 1) the energe of the frequency content of a signal and 2) time. Isn't two-dimensional more correct? Lova Falk ( talk) 16:10, 17 January 2008 (UTC)
From user Spectrum1234:
I say it is 3-D. Is very thin paper 2-D or 3-D (even when viewed on your 2-D monitor) ?
Look at these spectrum plots (90' and 60') from the Goldwave program of an extremely quiet noise burst (thus it is about as 2-D (flat) as it could be, yet) it still 'looks' like it is 3-D (to the extent possible on a 2-D monitor):
Someone should link this page to the italian corresponding article in italian, "Spettrogramma" —Preceding unsigned comment added by 151.67.178.125 ( talk) 11:42, 13 June 2009 (UTC)
Where sonograph redirects to this page, sonography redirects to medical ultrasonography. This does not seem consistent, should we change this? -- 130.89.139.73 ( talk) 13:26, 23 July 2009 (UTC)
These two voice spectrograms are awful, they use such a low frequency resolution that you cannot distinguish any of their sonorants, they appear all fused together, which is misleading, and doesn't show how the pitch of voice varies (doesn't show the pitch at all actually). -- 89.124.241.234 ( talk) 14:19, 13 November 2009 (UTC)
This edit added the following to the lead section: "In the field of time–frequency signal processing, it is one of the most popular quadratic Time-Frequency Distribution that represents a signal in a joint time-frequency domain and that has the property of being positive." Does that mean something to the regular contributors? Maybe there's just a simple typo throwing me off, but as a first-time visitor here, even with some experience with signal processing, I can't understand a word of it. For example, the terms "quadratic", "positive" and "distribution" are not defined, nor do they play much of a role in the article. Spiel496 ( talk) 17:44, 27 April 2011 (UTC)
They do not bear any apparent relation to the subject (spectrogram) or content of the article. Did some previous editor get confused between cryptograms and spectrograms? — Preceding unsigned comment added by 167.216.14.162 ( talk) 22:56, 15 September 2011 (UTC)
According to [3] a spectrogram is a "A graphic or photographic representation of a spectrum" - which is what I always understood the general term spectrogram means. For example you could have a spectrogram of the light observed from a star. This article gives the impression that a spectrogram is always related to sound waves. You can also find scientific papers ( [4]) citing the term spectrogram in relation to other spectra than just sound waves. 202.180.125.97 ( talk) 18:54, 2 October 2013 (UTC)
When you click this link under "External Links", it links to a page that doesn't exist. Can someone fix this maybe? 2601:8B:4400:C180:2048:CDF2:690E:727 ( talk) 01:33, 30 December 2015 (UTC)
Some recent edits have raised the issue again about how this Spectrogram article is restricted to sound while the Spectograph article seems more restricted to EM radiation. The sentence Kvng reverted is generally correct, albeit added without source. A spectogram is the output of a spectrograph, or someimtes the result of digital transformation of the input signal in a manner that is generally analogous to what a spectrograph does. Who wants to step up to resolve this? It requires an editor who can pull information from multiple disciplines. I'm happy to help, but don't think I can do the entire thing myself. —jmcgnh (talk) (contribs) 23:16, 22 August 2016 (UTC)
How would the resolution of a spectrogram obtained with a "series of band-pass filters" compare against that created conventionally via an FFT? Particularly in the low-mid audio frequency range. An FFT or a "digital" equalizer is quite poor at resolving narrow tones without compromising the time-resolution across the spectrum. I guess there must be a catch, because this type of filter isn't used anywhere. I would like to hear an explanation with minimal maths. J7n ( talk) 17:20, 11 February 2017 (UTC)
I am not aware of spectrograms that don't use time as one of their axis. Greglocock asserts that RPM can replace time and provides this citation. These plots have frequency, amplitude and RPM axis but there is no indication they're called or considered spectrograms. I have marked this with {{ fv}}. I think Greglocock would prefer if I just marked "or some other variable" in the lead with {{ cn}} but, like I said, I'm not aware of any spectrograms that don't use time and it is difficult to prove a negative. ~ Kvng ( talk) 15:34, 9 November 2017 (UTC)