Effect of DC Offset Correction - Louder?

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bdickens
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Re:Effect of DC Offset Correction - Louder? 2010/07/29 12:20:47 (permalink)
I'm going with the electronics engineer on this one.

Byron Dickens
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Beagle
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Re:Effect of DC Offset Correction - Louder? 2010/07/29 12:26:03 (permalink)
NoKey is technically correct about RMS, if you're talking about the electrical energy. But we're not talking about electrical energy; we're talking about acoustic energy. And a DC offset does not add to the acoustic energy of a signal coming from your monitors.

I still don't understand, however, why anyone can't give me a technical reference on how to use DC offset in an RMS calculation.  all of the formulas I know about and can find do not reference DC voltage.  I also know that if I have a signal on a scope (it does not have to be a pure sine wave) and I add DC offset to that signal, my RMS does not change simply because of the DC offset.  so I'm confused why several people here are telling me that DC offset is part of RMS and why no one will give me a reference on how to calculate it. 

but since we have driven this into the ground, and since it does not solve the OP's problem if we resolve the issue on how to calculate RMS, I will back out of this part of the conversation and focus on the problem that the OP has.

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#32
NoKey
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Re:Effect of DC Offset Correction - Louder? 2010/07/29 15:05:50 (permalink)
Beagle



Dear Beagle,

RMS is calculated from peak values ONLY when the wave is symmetrical, or sinusoidal.

Common sense should tell you that when a wave is not symmetrical there is NO way that just the peak can determine its energy contents.

all I'm asking, El, is that you show me the reference where you can find the DC value in the formula for determining the RMS value of a non-uniform waveform. 

I have not argued anywhere that you are incorrect when you say that a complex waveform is calculated by something more than Vpeak/sqrt2.  (technically for audio waveforms the RMS value is simply calculated as the average of the peak to peak).  I have said over and over again that it does not include DC offset in the calculations and you cannot convince me that it does by saying it's "common sense."  prove it with a reference and I will concede.  saying it's "common sense" is completely unacceptable for proof.

Larry - very sorry for sidetracking your problem.  in your experiments you say that SHS is playing them louder but not cooledit.  are you using your ears as the reference or are you looking at peak levels on your meters in SHS and cooledit and seeing that SHS has a new higher peak value?

Hi Beagle,

Why do you want me to make an effort that you are most capable of doing, specially if you really have the interest?...Just google it out with some impartiality.

I could do the googling, but but it is not my job to convince you.

Besides, you might think that I was biased.


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brundlefly
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Re:Effect of DC Offset Correction - Louder? 2010/07/29 15:10:49 (permalink)
Beagle



NoKey is technically correct about RMS, if you're talking about the electrical energy. But we're not talking about electrical energy; we're talking about acoustic energy. And a DC offset does not add to the acoustic energy of a signal coming from your monitors.

I still don't understand, however, why anyone can't give me a technical reference on how to use DC offset in an RMS calculation.  all of the formulas I know about and can find do not reference DC voltage.  I also know that if I have a signal on a scope (it does not have to be a pure sine wave) and I add DC offset to that signal, my RMS does not change simply because of the DC offset.  so I'm confused why several people here are telling me that DC offset is part of RMS and why no one will give me a reference on how to calculate it. 

but since we have driven this into the ground, and since it does not solve the OP's problem if we resolve the issue on how to calculate RMS, I will back out of this part of the conversation and focus on the problem that the OP has.

A straight mathematical RMS calculation automatically includes offset if there is any net offset from zero in the sample values you are plugging into the calculation. In the mathmatical realm, you have to explicitly subtract the offset from each value before you square it, or it will have an effect on the resulting RMS value. I can gin up a simple Excel spreadsheet that will demonstrate this, if you like

I'm not an electonics wizard so I don't know what's usual and customary for implementing Vrms measurements in meters and scopes, but it would not surprise me that some remove the offset, and some do not. If I had to guess, I would imagine most devices do exclude the DC component, and only show you the RMS of the variation (i.e. standard deviation). Apparently your scope is doing this.


post edited by brundlefly - 2010/07/29 15:14:11
#34
NoKey
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Re:Effect of DC Offset Correction - Louder? 2010/07/29 15:14:50 (permalink)
jcatena


1) Any ripple or variation in the DC is AC (like the audio) and could be heard. The DC itself can not be heard.
2) The DC in digital audio recordings, usually very small, is caused by drift in the zero offset of ADC input or preamps, and normally it only varies very slowly following temperature changes.
3) In 99.9% of audio amplifiers, DC is blocked. So normally the DC doesn't reach the speakers.
 
Hi jcatena,

But please do be aware that I am saying that a FAULTY component can be the cause of leakage, the blockage of DC that you talk about is based on all components being healthy.

I personally don't feel that DC offsets is a problem in current sounds being produced, though, either produced by pros or like amateur people like me.

Thanks for your inputs.


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Beagle
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Re:Effect of DC Offset Correction - Louder? 2010/07/29 15:22:44 (permalink)
As I said above - there's no point in continuing the debate on how to calculate RMS since it doesn't help the OP. 
post edited by Beagle - 2010/07/29 15:41:33

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brundlefly
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Re:Effect of DC Offset Correction - Louder? 2010/07/29 15:41:08 (permalink)

no one has still given a technical reference on how to include DC in the calculations anyway.



This may not be the most authoritative site, but here's a link to a page that clearly shows the difference between a straight RMS calculation, and one where you remove the offset by subtracting the average of the sample values, which is what a standard deviation calculation does. If you don't subtract that average of all values (the "offset" from zero) from each individual value before squaring, you get RMS, and it will vary with offset.


http://www.answers.com/topic/root-mean-square



But, as I said, this is in the mathematical and electrical realms, and is not applicable to acoustic signals.







post edited by brundlefly - 2010/07/29 15:42:36
#37
NoKey
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Re:Effect of DC Offset Correction - Louder? 2010/07/29 15:44:31 (permalink)
Beagle


As I said above - there's no point in continuing the debate on how to calculate RMS since it doesn't help the OP and because no one has still given a technical reference on how to include DC in the calculations anyway.

Hi Beagle,

Why do you want me to make an effort that you are most capable of doing, specially if you really have the interest?...Just google it out with some impartiality.

I could do the googling, but but it is not my job to convince you.

Besides, you might think that I was biased.

I have searched, Nokey and I can't find a reference to a calculation with DC included - you're the one making the assertion that it IS included, so the burden is on you to prove it.  besides - how does a technical reference that you supplied make it a biased reference unless you're the one who wrote it? 
Beagle, I even gave you the method to calculate it. It is even self descriptive in the name RMS, remember? ...I even told you that, paradoxically, first you Square the value of points in the wave, then you take the mean, and then you take the square root.

I also want to remind you that all waves that do not cross the X axis by force they have  a DC component.

Remember that even a sine wave, choped from the bottom, is the product of a rectifier, and that's DC..I can tell you that even though I am not an electronics engineer.

DC is just a name, my friend. In a wave, there is no real separation.

Also, it might help to realize that DC components are undesirable, except when intentional, of course.

And common sense, again would indicate that what we cal "DC offset" comes from faults, and faults come from faulty components.

If you take the oscillograph of any assymetrical wave you wouldn't even know just by looking what is the "DC offset". You'd have to take measurements of each point in the wave, as said. That obviously means that there is no way to IGNORE the DC component, because in the first place, you couldn't identify it.

What's called "DC" offset -IS- constitutes the wave as much as anything else.

That's why 'DC' offset is just a name.


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#38
NoKey
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Re:Effect of DC Offset Correction - Louder? 2010/07/29 15:53:34 (permalink)
brundlefly



no one has still given a technical reference on how to include DC in the calculations anyway.



This may not be the most authoritative site, but here's a link to a page that clearly shows the difference between a straight RMS calculation, and one where you remove the offset by subtracting the average of the sample values, which is what a standard deviation calculation does. If you don't subtract that average of all values (the "offset" from zero) from each individual value before squaring, you get RMS, and it will vary with offset.


http://www.answers.com/topic/root-mean-square



But, as I said, this is in the mathematical and electrical realms, and is not applicable to acoustic signals.

Yes, that's one of them, and I believe that is called the Simpson's formula.


As to denying that it does not apply to acoustical waves that would be a prerogative.



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Re:Effect of DC Offset Correction - Louder? 2010/07/29 15:55:59 (permalink)

I even told you that, paradoxically, first you Square the value of points in the wave, then you take the mean, and then you take the square root.



ahhhhrrrrrg! This is so screwed up, it's just going to confuse the issue. You left out summing the squares and dividing the sum by the number of values, and you included calculating the mean, but didn't say what you do with it. 

If you want StDev (i.e. RMS of the deviations from the mean), you subtract that mean from each value before squaring, and if want a simple RMS, you pay no attention to the mean, which I thought was what you are trying to express. 
post edited by brundlefly - 2010/07/29 16:00:29
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larrymcg
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Re:Effect of DC Offset Correction - Louder? 2010/07/29 15:56:58 (permalink)
More experiments from the OP:

I noted in my previous post that clicking the audio with the split tool caused the playback to become louder.  I've also noticed that UNDOing the split reverts to playback to the lower volume.

Exporting the track to a wav (with all processing and automation, etc. turned off) creates a wav that plays back at the louder volume (playback in CoolEdit).

Doing a COPY on the original track leaves it playing at the lower volume.

Copying the audio and pasting into a new audio track (in the same project) produces a track that plays at the louder volume.  And the track from which the copy was made ALSO plays louder.

In fact, just inserting a new audio track (with no COPY or PASTE operation) causes the original audio to play louder.  UNDOing the insert causes the original track to play softer.

Copying the original track and pasting into a new project results in a new track that plays louder.

I went back to the PA9 project and noted that the volume sliders on the main output bus were set at -6db.  Then I exported the track of interest (from PA9) with the sliders at -6db and also at 0db.  I listened to them in CoolEdit.  The one for -6db sounds like the audio in SHS7 playing at the lower volume.  The one from PA9 with sliders at 0db sounds like the one in SHS7 after removing the DC offset or clicking it with the split tool.

So then I created a new SHS7 project and imported the wave from PA9 that had the sliders at -6db.  The audio plays at the lower volume (as expected).  Removing the DC Offset and clicking with the split tool DOES NOT cause the playback to become louder - it continues to play at the lower volume.

I think I'm at the end of my ideas on experiments.  SHS7 is just being weird about the audio from the bun file.

--Larry


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Beagle
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Re:Effect of DC Offset Correction - Louder? 2010/07/29 16:06:03 (permalink)
brundlefly and Nokey:  I suggest (again) that we discontinue arguing about how to calculate RMS.  it does not solve the OP's problem (although I will take this time to concede to both of you that I have found technical reference to DC values affecting RMS and therefore I admit I was wrong and I apologize).

Larry - I suspect that part of the problem may be in the panning laws.  but again I ask (you probably missed it above because of the distractions about RMS calculations) how do you perceive this extra loudness?  by ear, by meters or other?
post edited by Beagle - 2010/07/29 16:11:00

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#42
NoKey
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Re:Effect of DC Offset Correction - Louder? 2010/07/29 16:15:31 (permalink)
Hi Larry, thanks for sharing the efforts.

Seems to me that you'd need to take a NEW, clean project, no effects, nothing special, and import the original specimen wave into it, just as you did it to the wave gotten from PA9.

Has that been done?

Thank you.



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#43
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Re:Effect of DC Offset Correction - Louder? 2010/07/29 16:19:05 (permalink)
Beagle


brundlefly and Nokey:  I suggest (again) that we discontinue arguing about how to calculate RMS.  it does not solve the OP's problem (although I will take this time to concede to both of you that I have found technical reference to DC values affecting RMS and therefore I admit I was wrong).

Larry - I suspect that part of the problem may be in the panning laws.  but again I ask (you probably missed it above because of the distractions about RMS calculations) how do you perceive this extra loudness?  by ear, by meters or other?
Agreed. Just trying to help resolve the miscommunication. And I think it is important to have some consensus that correcting what is probably a tiny DC offset can't account for the kind of level change being reported.


The pan law issue would be a good thing to consider, but I don't know if that could account for everything the OP is reporting, either. This is one of those issues that could be a real brain teaser without the advantage of being able to lay hands on the system and check every variable.


#44
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Re:Effect of DC Offset Correction - Louder? 2010/07/29 16:23:05 (permalink)
brundlefly


Beagle


brundlefly and Nokey:  I suggest (again) that we discontinue arguing about how to calculate RMS.  it does not solve the OP's problem (although I will take this time to concede to both of you that I have found technical reference to DC values affecting RMS and therefore I admit I was wrong).

Larry - I suspect that part of the problem may be in the panning laws.  but again I ask (you probably missed it above because of the distractions about RMS calculations) how do you perceive this extra loudness?  by ear, by meters or other?
Agreed. Just trying to help resolve the miscommunication. And I think it is important to have some consensus that correcting what is probably a tiny DC offset can't account for the kind of level change being reported.


The pan law issue would be a good thing to consider, but I don't know if that could account for everything the OP is reporting, either. This is one of those issues that could be a real brain teaser without the advantage of being able to lay hands on the system and check every variable.

I agree completely.

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#45
jcatena
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Re:Effect of DC Offset Correction - Louder? 2010/07/29 16:27:32 (permalink)
RMS is electrical energy, the integration of the signal over time, i.e. the area covered by the graphic representation. A RMS meter will certainly be affected by a DC signal.
It will not affect sound, except if the DC offset is translated through the whole chain and it is very large, it which case it will limit the maximum peak in one side, i.e. clipping will occur at a lower peak-to-peak magnitude. 
Where do you guys learn so much nonsense? And why do you write absurd things if you have no idea of what are you talking about?
I don't need to put links or anything, for me this is like if you asked me to prove that 2+2=4, so if you care look for documentation yourself, i don't care. For things like this consider that i'm like god and you're like an ape ;)



Jose Catena
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#46
NoKey
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Re:Effect of DC Offset Correction - Louder? 2010/07/29 16:28:48 (permalink)
brundlefly



I even told you that, paradoxically, first you Square the value of points in the wave, then you take the mean, and then you take the square root.



ahhhhrrrrrg! This is so screwed up, it's just going to confuse the issue. You left out summing the squares and dividing the sum by the number of values, and you included calculating the mean, but didn't say what you do with it. 

If you want StDev (i.e. RMS of the deviations from the mean), you subtract that mean from each value before squaring, and if want a simple RMS, you pay no attention to the mean, which I thought was what you are trying to express. 

Hi Brundlefly,

In RMS, M(ean is the summation divided by the number of components in the summation. It is not left out.

Simpson's is, as far as I recall, only an adequate approximation of an integration, but it should reflect pretty much the RMS definition.

Sorry if I left any thing out, or am not clear on some thing. Some is the nature of things, but mostly it's my being rusty and white in places.

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#47
NoKey
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Re:Effect of DC Offset Correction - Louder? 2010/07/29 16:48:31 (permalink)
Beagle


brundlefly and Nokey:  I suggest (again) that we discontinue arguing about how to calculate RMS.  it does not solve the OP's problem (although I will take this time to concede to both of you that I have found technical reference to DC values affecting RMS and therefore I admit I was wrong and I apologize).

Larry - I suspect that part of the problem may be in the panning laws.  but again I ask (you probably missed it above because of the distractions about RMS calculations) how do you perceive this extra loudness?  by ear, by meters or other?
Beagle,

Good take you do.

The effort not to take  things personal, nor to offer them as such is a good principle...Specially in knowledge that has been inherited from others.

I knew you were joking when you interviewed me about my technical background, because I've been retired from my profession for like two decades, and surely you are not recruiting.

Best of all, friend.


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Beagle
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Re:Effect of DC Offset Correction - Louder? 2010/07/29 16:52:25 (permalink)
NoKey


Beagle


brundlefly and Nokey:  I suggest (again) that we discontinue arguing about how to calculate RMS.  it does not solve the OP's problem (although I will take this time to concede to both of you that I have found technical reference to DC values affecting RMS and therefore I admit I was wrong and I apologize).

Larry - I suspect that part of the problem may be in the panning laws.  but again I ask (you probably missed it above because of the distractions about RMS calculations) how do you perceive this extra loudness?  by ear, by meters or other?
Beagle,

Good take you do.

The effort not to take  things personal, nor to offer them as such is a good principle...Specially in knowledge that has been inherited from others.

I knew you were joking when you interviewed me about my technical background, because I've been retired from my profession for like two decades, and surely you are not recruiting.

Best of all, friend.

No hard feelings to you.
 
for Jose, however, I can't say the same.  Too bad some people have to act like jerks.

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#49
NoKey
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Re:Effect of DC Offset Correction - Louder? 2010/07/29 16:59:40 (permalink)
jcatena


RMS is electrical energy, the integration of the signal over time, i.e. the area covered by the graphic representation. A RMS meter will certainly be affected by a DC signal.
It will not affect sound, except if the DC offset is translated through the whole chain and it is very large, it which case it will limit the maximum peak in one side, i.e. clipping will occur at a lower peak-to-peak magnitude. 
Where do you guys learn so much nonsense? And why do you write absurd things if you have no idea of what are you talking about?
I don't need to put links or anything, for me this is like if you asked me to prove that 2+2=4, so if you care look for documentation yourself, i don't care. For things like this consider that i'm like god and you're like an ape ;)
Your problem would be that apes don't believe in God.  And I know from personal experience that 2 + 2 is not 4, except in theory.

And although you make good technical points, I thank you. But I wouldn't adore you. Bananas and peanuts, YES! I adore those.


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larrymcg
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Re:Effect of DC Offset Correction - Louder? 2010/07/29 17:27:42 (permalink)
Beagle,

How do I perceive the louder volume?  I hear it -- it is quite obvious.  And the SHS7 playback meters for the audio track and for the main output bus show it.

The audio waveform (displayed by SHS7 zoomed in both vertically and horizontally) does not change at all when I use the split tool but the volume levels go up (in my ear and in the level meters).

When I use the DC Offset Removal tool, the waveform doesn't change shape but it does move up so that the center of the waveform is on the -infinity db line.  It sounds louder and the meters show the higher level.

I can't tell any difference in the loudness when comparing the results of clicking with the split tool or removing the DC Offset.

Panning laws?  I don't know about panning laws.  In any case, this is a mono recording with no panning going on.  

The track is being played back through the stereo main output bus and sounds dead center.  However, the results are the same if played back through the left mono main output bus (except that the sound is all the way to the left, as expected).

NoKey,

The most "original" version of this track is the one in the PA9 project.  So it is not really the very first original version of the recording.  It was manipulated in PA9 and the truly unmodified original doesn't exist.  (I've learned to keep the originals!)

I've been thinking about this recording.  It is many years old, I think 3 PCs ago (WinMe and PA9).  That was a Compaq PC with a cheapie PCI sound card that generated a noise level that could be heard in the dead spots.  It looks to me that I used PA9 to normalize the audio (I didn't have CoolEdit then).  PA9 can only maximize to 100% (i.e., highest peaks go to 0db) and it does not remove DC Offset.  That's exactly what I see in the waveform in PA9 and in SHS7 as it comes in from the bun file.  It's normalized to 100% and has audible noise.

The audio as shown in PA9 and in SHS7 both have the same DC Offset.

--Larry


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#51
Beagle
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Re:Effect of DC Offset Correction - Louder? 2010/07/29 17:37:43 (permalink)
hey, larry - how much difference is there (you say you can hear a difference, so I'm thinking it's got to be at least 1-2dB but you say it's clearly audible, so much more?)

also, what are the specs of that audio clip?  44100Hz?  16bit?  wave file?  or what?

there are no FX on this track, correct?

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brundlefly
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Re:Effect of DC Offset Correction - Louder? 2010/07/29 17:45:17 (permalink)
In RMS, M(ean is the summation divided by the number of components in the summation. It is not left out.



Duh. Of course. My turn to eat some hat. Got to a point where I couldn't see the forest for the trees in this thread. 


And now back to our regularly scheduled programming... 
#53
larrymcg
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Re:Effect of DC Offset Correction - Louder? 2010/07/29 19:06:30 (permalink)
Beagle,

It's on the order of 6db.  I arrived at that my moving the volume slider by 6db and it seemed to sound pretty close.

The original recording (actually, all my recordings) are 44100, 16bit.  PA9 (like SHS7) keeps the audio as wav files.

There are no effects.  The audio track is routed directly to the output bus.

--Larry

PS:  I think I can post a couple screen shots showing part of the waveform before and after DC Offset removal.  I have also recorded the before and after versions and I have a screen shot showing how much bigger the waveform is for the recording of the "after" version.  I'll do those in a separate post.


Intel Core i7-4790 @3.6GHz; 8GB; Win10 Pro 64bit; 1TB disk + 3TB ext disk; Midiman Fineline mixer; MidiSport 4x4 midi I/F; Roland JV-30 kbd/synth; Yamaha TG55 synth; Rx with 3 piece Home audio speakers; Sonar X3e Studio
#54
NoKey
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Re:Effect of DC Offset Correction - Louder? 2010/07/29 19:23:26 (permalink)
larrymcg


Beagle,

How do I perceive the louder volume?  I hear it -- it is quite obvious.  And the SHS7 playback meters for the audio track and for the main output bus show it.

The audio waveform (displayed by SHS7 zoomed in both vertically and horizontally) does not change at all when I use the split tool but the volume levels go up (in my ear and in the level meters).

When I use the DC Offset Removal tool, the waveform doesn't change shape but it does move up so that the center of the waveform is on the -infinity db line.  It sounds louder and the meters show the higher level.

I can't tell any difference in the loudness when comparing the results of clicking with the split tool or removing the DC Offset.

Panning laws?  I don't know about panning laws.  In any case, this is a mono recording with no panning going on.  

The track is being played back through the stereo main output bus and sounds dead center.  However, the results are the same if played back through the left mono main output bus (except that the sound is all the way to the left, as expected).

NoKey,

The most "original" version of this track is the one in the PA9 project.  So it is not really the very first original version of the recording.  It was manipulated in PA9 and the truly unmodified original doesn't exist.  (I've learned to keep the originals!)

I've been thinking about this recording.  It is many years old, I think 3 PCs ago (WinMe and PA9).  That was a Compaq PC with a cheapie PCI sound card that generated a noise level that could be heard in the dead spots.  It looks to me that I used PA9 to normalize the audio (I didn't have CoolEdit then).  PA9 can only maximize to 100% (i.e., highest peaks go to 0db) and it does not remove DC Offset.  That's exactly what I see in the waveform in PA9 and in SHS7 as it comes in from the bun file.  It's normalized to 100% and has audible noise.

The audio as shown in PA9 and in SHS7 both have the same DC Offset.

--Larry
Hi Larry,

what I meant is this, basically: If you make a new project, no templates; even close the one that Sonar starts with, and for a basic one, then to an audio track import the audio track that did manifest the problem, does the problem still manifest?

Does the problem still manifest, same conditions, on another audio file?

I think this would help establis whether it is Sonar or the file which relates to the problem, or to perhaps the template that typically starts with Sonar, or if no template, some settings.

I find it  indeed strange, and am interested in what causes the problem. I also believe that it should be possible to decipher where the trouble factor is coming from.

I hope you have a way and thank you for sharing that finding.

Thanks.


Songs I've produced with Sonar LE: http://www.soundclick.com...ult.cfm?bandID=1086857
#55
larrymcg
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Re:Effect of DC Offset Correction - Louder? 2010/07/29 19:29:22 (permalink)
Here are 3 screen shots.
The first shows the first part of the audio before applying DC Offset.  You can see that the signal is offset below the center line.


Here is the same thing after doing DC Offset removal:

You can see (I hope) that the signal looks the same except it has moved up.

Here is a shot that shows 3 waveforms in the track view.  I recorded the playback of the track in question twice.  First before doing DC Offset removal and then after doing the removal.  You can see (I hope) that the "after" version is much larger than the before version.

The "after" recording looks like the first track whereas the "before" recording looks much smaller (and sounds smaller).
However, the first track looks about the same before and after the DC Offset removal

--Larry


Intel Core i7-4790 @3.6GHz; 8GB; Win10 Pro 64bit; 1TB disk + 3TB ext disk; Midiman Fineline mixer; MidiSport 4x4 midi I/F; Roland JV-30 kbd/synth; Yamaha TG55 synth; Rx with 3 piece Home audio speakers; Sonar X3e Studio
#56
Beagle
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Re:Effect of DC Offset Correction - Louder? 2010/07/29 19:50:51 (permalink)
larry - how big are these clips (file size)?  can you send them to me and let me do the same things to them in sonar and see if they behave the same or if I can see something different with the clips?

http://soundcloud.com/beaglesound/sets/featured-songs-1
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#57
Lanceindastudio
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Re:Effect of DC Offset Correction - Louder? 2010/07/29 20:28:51 (permalink)
Wow I had to open some wine and lay back and enjoy this one! hahaha

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#58
larrymcg
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Re:Effect of DC Offset Correction - Louder? 2010/07/30 01:17:19 (permalink)
Hi Larry,

what I meant is this, basically: If you make a new project, no templates; even close the one that Sonar starts with, and for a basic one, then to an audio track import the audio track that did manifest the problem, does the problem still manifest?
>>>>I've tried getting the audio track into another project in various ways.  It always shows up playing at the louder volume.  I even tried opening the bun file in SHS7 and saving it as a cwb (Sonar bun file).  The audio track in the cwb plays at the louder volume.  It seems that doing most anything to the problematic audio causes the symptoms to go away.

Does the problem still manifest, same conditions, on another audio file?
>>>>I thought I had one other example but I'm having a hard time finding it.  So I'm not sure.  I have other bun files from PA9 that have DC Offset but they do not manifest the problem.

I think this would help establis whether it is Sonar or the file which relates to the problem, or to perhaps the template that typically starts with Sonar, or if no template, some settings.

I find it  indeed strange, and am interested in what causes the problem. I also believe that it should be possible to decipher where the trouble factor is coming from.

I hope you have a way and thank you for sharing that finding.

Thanks.




Intel Core i7-4790 @3.6GHz; 8GB; Win10 Pro 64bit; 1TB disk + 3TB ext disk; Midiman Fineline mixer; MidiSport 4x4 midi I/F; Roland JV-30 kbd/synth; Yamaha TG55 synth; Rx with 3 piece Home audio speakers; Sonar X3e Studio
#59
larrymcg
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Re:Effect of DC Offset Correction - Louder? 2010/07/30 01:34:14 (permalink)
Beagle,

The bun file is pretty big (around 54MB).  Any form of saving the bun file results in a file that does not have the symptoms so I've not found a way to make the bun file smaller and still manifest the symptoms.

I have discovered something.  I can go back to the PA9 wrk file and save it again as a bun and I consistently get the problem.  That PA9 wrk file (and almost all the other wrk files I have converted to bun files) has some effects active in it.  If I first delete the effects from the wrk file and then save as a bun, the bun is fine (no problems) when opened in SHS7.  The effects in the wrk file are not available to SHS7 so placeholders appear.  However, that is true of all the other wrk files I have converted to bun files.  And they are all OK (although I think I recall one other problematic bun file).  So it's still not clear to me what is different about this one.

I'm not sure it is worth chasing this issue down.  It is easy for me to recognize it and make it go away.  I'm sure there are other weird things that can happen when converting a PA9 wrk file to a bun file and then opening them in SHS7.  In fact, I know of some others but I can deal with them too.

It's not too difficult to send a 54MB file to you (I use YouSendIt) or I could put it on my website and make it public so you could download it.

--Larry


Intel Core i7-4790 @3.6GHz; 8GB; Win10 Pro 64bit; 1TB disk + 3TB ext disk; Midiman Fineline mixer; MidiSport 4x4 midi I/F; Roland JV-30 kbd/synth; Yamaha TG55 synth; Rx with 3 piece Home audio speakers; Sonar X3e Studio
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