Go Back   Home > Forums > Member Areas > The Lounge

The Lounge A place to talk about almost anything but politics and religion.

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 16th August 2012, 08:51 PM   #26461
diyAudio Member
 
scott wurcer's Avatar
 
Join Date: Jan 2004
Location: cambridge ma
Quote:
Originally Posted by jneutron View Post
The one method of localization?? You have lost me.
Please! I'm not Ed's doppleganger.
__________________
“The earth's rotation will slow within days and stop for several days just prior to the pole shift. This is when you and your loved ones should be situated at your safe location.”
  Reply With Quote
Old 16th August 2012, 08:55 PM   #26462
diyAudio Member
 
jneutron's Avatar
 
Join Date: Jan 2004
Location: away
Quote:
Originally Posted by simon7000 View Post
John,

That is known as Flanging because it was originally done with phase locked tape players and by changing the drag on just one you got the effect.
Yes, I know..perhaps that is why I called it phasing/flanging?

We are not talking about those issues. I suspect that getting the records out of sync by 10 usec would be really difficult![/quote]
No, it is not difficult. The comb filtering was so good that when I inverted one program, total and absolute cancellation of ALL program occurred..A stereo with 3 kilowatts running to clipping going absolutely silent. Remember toto, we're not talking digital here so we ain't in Kansas....nuttin but analog back in the day.

jn

ps..I did try slowing down my 10 inch reel to reel by dragging the flange back in '79. Broke the tape..so started buying two copies of the hot songs, for phasing/flanging and echo.

Last edited by jneutron; 16th August 2012 at 08:58 PM.
  Reply With Quote
Old 16th August 2012, 08:58 PM   #26463
diyAudio Member
 
scott wurcer's Avatar
 
Join Date: Jan 2004
Location: cambridge ma
Quote:
Originally Posted by simon7000 View Post

Noise and music are non-periodic so they cannot be reduced to a Fourier series.

Let me know what you don't understand.

This statement on it's its own has little or no relevance. Please address a particular technique or analysis whose results you find invalid due to the above "fact". The implication that Fourier techniques have no use with noise and music is as your friend said "silly". A finite time sample bounds our knowledge of the stimulus. A priori you have no way of knowing that your input is NOT periodic. The pointless dissing of useful tools is tiresome.
__________________
“The earth's rotation will slow within days and stop for several days just prior to the pole shift. This is when you and your loved ones should be situated at your safe location.”
  Reply With Quote
Old 16th August 2012, 09:02 PM   #26464
diyAudio Member
 
Wavebourn's Avatar
 
Join Date: Sep 2006
Location: Pleasant Hill, CA
Send a message via Skype™ to Wavebourn
I did this effect with Roland flanger pedal, inserting it in a left master channel of mixing console. It was used as delay only, no mixing, no feedback, with floating delay time. I was switching it on during solo of the drummer. There were no flanger effects, just people rotated heads all around. Some even heard vertical image movements!
__________________
"Our youth [...] have bad manners, contempt for authority; they show disrespect for their elders, contradict their parents, [...] and tyrannize their teachers.” -- Plato, 447-367 BCE
  Reply With Quote
Old 16th August 2012, 09:08 PM   #26465
DF96 is offline DF96  England
diyAudio Member
 
Join Date: May 2007
Quote:
Originally Posted by simon7000
A first order CR filter increase distortion by reducing the level of the fundamental even on periodic signals is one issue.

A non periodic signal that does not have a derivative that is similar to itself will also distort. A sin has cosine so there is only phase shift in those cases.

Noise and music are non-periodic so they cannot be reduced to a Fourier series.

Let me know what you don't understand.
The first two sentences appear to be a statement of your beliefs. A CR filter can certainly modify the relative amplitudes (and phases) of existing components by acting as a tone control. The output may sound different from the input, simply because of this. Your second sentence is untrue. Differentiation is a linear operation so it does not distort; it acts just like an extreme tone control.

Noise and music if unrepeated are non-periodic so cannot be reduced to a Fourier series, but they can be handled by a Fourier transform which is the continuous (in frequency) development of the Fourier series (which is discrete in frequency). By repeating the noise/music they become periodic so can be handled by a Fourier series. The continuous Fourier transform splits into closely-spaced Fourier series components. Unless your circuits behave differently when music is repeated rather than played just once then the results of one analysis can be carried over into the other.

So you misunderstood, and so presumably misrepresented, what we are saying. You also stated your false idea about CR circuits, which if your friend agreed with would be a sign that he doesn't understand either.
  Reply With Quote
Old 16th August 2012, 09:39 PM   #26466
diyAudio Member
 
Join Date: Nov 2008
Location: Oakmont PA
Quote:
Originally Posted by scott wurcer View Post
This statement on it's its own has little or no relevance. Please address a particular technique or analysis whose results you find invalid due to the above "fact". The implication that Fourier techniques have no use with noise and music is as your friend said "silly". A finite time sample bounds our knowledge of the stimulus. A priori you have no way of knowing that your input is NOT periodic. The pointless dissing of useful tools is tiresome.
Scott,

You certainly can put any signal in a Fourier based analyzer. You will get information to the limits of your technique.

Now one can certainly take the Fourier coefficients of sign wave or series of them and with very little information do an accurate reproduction. But if you wiggle the level control you have a nonperiodic signal that is not so simply reduced.

Now how would you capture the wiggle?
  Reply With Quote
Old 16th August 2012, 09:41 PM   #26467
DF96 is offline DF96  England
diyAudio Member
 
Join Date: May 2007
I sense wriggling, rather than wiggling.
  Reply With Quote
Old 16th August 2012, 09:46 PM   #26468
diyAudio Member
 
Join Date: Nov 2008
Location: Oakmont PA
DF

When you subtract the level matched input from the output what is left is distortion. For those who don't consider differences in wave shape you can just use the magnitude of the Fourier transform.

I thought you had posted before that noise and music are periodic!
  Reply With Quote
Old 16th August 2012, 09:48 PM   #26469
diyAudio Member
 
Join Date: Nov 2008
Location: Oakmont PA
Quote:
Originally Posted by DF96 View Post
I sense wriggling, rather than wiggling.
I sense lack of comprehension and silly arrogance!
  Reply With Quote
Old 16th August 2012, 09:49 PM   #26470
SY is offline SY  United States
diyAudio Moderator
 
SY's Avatar
 
Join Date: Oct 2002
Location: Chicagoland
Blog Entries: 1
Quote:
Originally Posted by simon7000 View Post
Noise and music are non-periodic so they cannot be reduced to a Fourier series.
Ah, now it's clear what you left out of your description. To further Dave's clear analysis, the system under test doesn't even have to play the same thing twice the same way- as long as you formally take f(t1) = f(t1 + nt0) where t0 is equal or greater to the sequence length and n is an integer, the mathematics is satisfied. Again, that doesn't even have to be done in the calculation, it's purely formalism.

There's a few hundred thousand FT spectrometers out there which work perfectly in defiance of your misunderstanding.
__________________
"The way to deal with superstition is not to be polite to it, but to tackle it with all arms, and so rout it, cripple it, and make it forever infamous and ridiculous."- H. L. Mencken
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



New To Site? Need Help?

All times are GMT. The time now is 08:11 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright ©1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2