Graphical Audio Representations at DVinfo.net

Harry Simpson · January 1st, 2011, 09:34 PM

I've been doing tests this evening of two lavs, a Sennheiser and AT mics. Below is the graphic of timeline from Sony Vegas Studio 10 HD.
The Sennheiser and AT mics looked liked they are flatlined yet the audio sounds fine and loud. All of these sound about the same volume but the graphic would lead me to believe otherwise.

How does one interpret a "good" audio graph visually? I'm used to seeing something more like the bottom timeline.....

Chad Johnson · January 1st, 2011, 10:16 PM

The visual blobs you see should correlate with the signal shown in the master output meter. If it's close to flat, that should be reflected when you solo that track and look at the bobbing meters. Maybe you are monitoring really loud. If the meters show you are peaking at a high level when the blobs are flat there's something strange. Did you possibly turn on a track effect like the compressor and turn up the level with that?

It does look like you could turn up your recording level on a couple tracks. Also I believe in Vegas you can grab the top of a clip, or turn on something that allows you to grab part of the clip and drag the clip volume up, and the visual blobs should visually increase as well. It's hard to say what's going on without digging around the project myself.

Harry Simpson · January 1st, 2011, 10:56 PM

Vegas will let you pull down the audio but can't increase it. The graphic representation sometimes will look like a good vertical height spread and other times it looks flatlined. I'd think the flatlined audio would be very soft or non-existent....yet it can sound just fine.

Jim Andrada · January 2nd, 2011, 12:34 AM

Hi Harry

Are you sure the limiters weren't cutting in and flattening the signal just before it clipped?

Were you in a club with a REALLY loud drum/bass?

Hard to really say without seeing a close up of just the track you're talking about - in fact if you could stretch this track vertically and show a screen shot it would let us see how close it's really getting to 0dB

Harry Simpson · January 2nd, 2011, 02:05 PM

Thanks Jim

Mics at "90" recording level on Zoom H4N were:
Sennheiser e365 XLR 48 using phantom power
Audio Technica 29 HE XLR dynamic (no phantom power)
MXL FR350 Lav XLR 48 using phantom power
MXL FR351 Lav XLR 48 using phantom power
Zoom H4N x/y stereo mics

The audio technica sounded fainter at "90" but the other mics sounded about the same with the Sennheiser and the smaller MXL FR350 Lav had the best cleanest sound. The lav mics of course were mid/upper chest mounted. The Senn and AT and Zoom were recorded at overhead boom pointed down agbout 12-15" above speaker.

I wouldn't think the grapgh would differ so much with the "recording level" all at "90"......

Chad Johnson · January 2nd, 2011, 03:31 PM

But within vegas, do the quiet LOOKING clips sound as loud as the clips with full looking waveforms? Or are you saying that when they were recording the levels looked good, and now they look to low?

Also, (not that it applies here) you can adjust the view of the waveforms in the timeline so you can see them more for reference purposes. But turned all the way down shows an accurate representation of the waveform.

Harry Simpson · January 2nd, 2011, 05:10 PM

Quote:

Originally Posted by Chad Johnson

But within vegas, do the quiet LOOKING clips sound as loud as the clips with full looking waveforms? .

Yes that's what i'm saying. The Audio Technica sounds weaker but the others even though looking like they are mainly flat lining are plenty loud.....

Jim Andrada · January 3rd, 2011, 01:59 AM

Hmmm. Sounds strange to me. Any way you could link to the clips or 10 or 20 seconds of them so I could download them and fool with them a bit?

I've seen things like this when recording different instruments - ie the plots will look different but the instruments will seem to have the same loudness.Perceived loudness doesn't necessarily correlate with peak volume, but if all the mics were recording pretty much the same material with consistent settings I don't have any ready explanation.

Rick Reineke · January 3rd, 2011, 12:12 PM

I can see by the screen-shot of Vegas, there's at least one audio plug-in assigned to each channel. Though it does not alter the visual waveform, If you up render and upload the audio, delete the plug-ins beforehand.

Off topic: The screen-shot of Vegas was most likely the 'default' plug-in chain: Compressor, Gate and whatever the third default plug-in was that SCS deemed 'necessary' for every track and 'one size fits all'.
I would advise any Vegas user to remove the audio plug-ins and change the default. Add plug-ins only when necessary.

Harry Simpson · January 3rd, 2011, 02:08 PM

Jim

Do you have Vegas Movie Studio or should I just save a sample of each off to .wav file and send to you?

The full audio track for each has me talking at 90, 80, 70, and 60 levels.

And yes these are the default FX applied to every sound and I'll remove them from defaults and before saving off to .WAV files.

Jim I'll save off to .WAVs and name them appropriately and send as an attachment to email - think i still have your email.

Thanks
Harry

Jim Andrada · January 3rd, 2011, 06:30 PM

Great -

I have the full Vegas /Sound Forge combo but .wav would be fine

January 1st, 2011, 09:34 PM	#1
Harry Simpson Major Player Join Date: Aug 2009 Location: Nashville, TN. Posts: 581	Graphical Audio Representations I've been doing tests this evening of two lavs, a Sennheiser and AT mics. Below is the graphic of timeline from Sony Vegas Studio 10 HD. The Sennheiser and AT mics looked liked they are flatlined yet the audio sounds fine and loud. All of these sound about the same volume but the graphic would lead me to believe otherwise. How does one interpret a "good" audio graph visually? I'm used to seeing something more like the bottom timeline..... Attached Thumbnails __________________ Nashville TN using Canon 5D MK3, Canon 550D, RODE SVM mic, 70-200 f2.8L II IS, 24-105 f4L IS, 50 and 85 f/1.8, Vegas Pro 11, Zoom H4n, Blackbird, Lilliput Monitor, Lightroom

January 1st, 2011, 10:16 PM	#2
Chad Johnson Major Player Join Date: Apr 2009 Location: Arcata, Ca Posts: 750	The visual blobs you see should correlate with the signal shown in the master output meter. If it's close to flat, that should be reflected when you solo that track and look at the bobbing meters. Maybe you are monitoring really loud. If the meters show you are peaking at a high level when the blobs are flat there's something strange. Did you possibly turn on a track effect like the compressor and turn up the level with that? It does look like you could turn up your recording level on a couple tracks. Also I believe in Vegas you can grab the top of a clip, or turn on something that allows you to grab part of the clip and drag the clip volume up, and the visual blobs should visually increase as well. It's hard to say what's going on without digging around the project myself. __________________ My Work: http://www.youtube.com/ChadWork1 Sony FS5 :: Panasonic GH4 :: Sony PMW-EX1 :: FCPx :: AT4053b :: Rode NTG-3,

January 1st, 2011, 10:56 PM	#3
Harry Simpson Major Player Join Date: Aug 2009 Location: Nashville, TN. Posts: 581	Vegas will let you pull down the audio but can't increase it. The graphic representation sometimes will look like a good vertical height spread and other times it looks flatlined. I'd think the flatlined audio would be very soft or non-existent....yet it can sound just fine. __________________ Nashville TN using Canon 5D MK3, Canon 550D, RODE SVM mic, 70-200 f2.8L II IS, 24-105 f4L IS, 50 and 85 f/1.8, Vegas Pro 11, Zoom H4n, Blackbird, Lilliput Monitor, Lightroom

January 2nd, 2011, 02:05 PM	#5
Harry Simpson Major Player Join Date: Aug 2009 Location: Nashville, TN. Posts: 581	Thanks Jim Mics at "90" recording level on Zoom H4N were: Sennheiser e365 XLR 48 using phantom power Audio Technica 29 HE XLR dynamic (no phantom power) MXL FR350 Lav XLR 48 using phantom power MXL FR351 Lav XLR 48 using phantom power Zoom H4N x/y stereo mics The audio technica sounded fainter at "90" but the other mics sounded about the same with the Sennheiser and the smaller MXL FR350 Lav had the best cleanest sound. The lav mics of course were mid/upper chest mounted. The Senn and AT and Zoom were recorded at overhead boom pointed down agbout 12-15" above speaker. I wouldn't think the grapgh would differ so much with the "recording level" all at "90"...... Attached Thumbnails __________________ Nashville TN using Canon 5D MK3, Canon 550D, RODE SVM mic, 70-200 f2.8L II IS, 24-105 f4L IS, 50 and 85 f/1.8, Vegas Pro 11, Zoom H4n, Blackbird, Lilliput Monitor, Lightroom

January 2nd, 2011, 03:31 PM	#6
Chad Johnson Major Player Join Date: Apr 2009 Location: Arcata, Ca Posts: 750	But within vegas, do the quiet LOOKING clips sound as loud as the clips with full looking waveforms? Or are you saying that when they were recording the levels looked good, and now they look to low? Also, (not that it applies here) you can adjust the view of the waveforms in the timeline so you can see them more for reference purposes. But turned all the way down shows an accurate representation of the waveform. __________________ My Work: http://www.youtube.com/ChadWork1 Sony FS5 :: Panasonic GH4 :: Sony PMW-EX1 :: FCPx :: AT4053b :: Rode NTG-3,

January 2nd, 2011, 12:34 AM	#4
Jim Andrada Inner Circle Join Date: Feb 2007 Location: Tucson AZ Posts: 2,211	Hi Harry Are you sure the limiters weren't cutting in and flattening the signal just before it clipped? Were you in a club with a REALLY loud drum/bass? Hard to really say without seeing a close up of just the track you're talking about - in fact if you could stretch this track vertically and show a screen shot it would let us see how close it's really getting to 0dB

January 3rd, 2011, 01:59 AM	#8
Jim Andrada Inner Circle Join Date: Feb 2007 Location: Tucson AZ Posts: 2,211	Hmmm. Sounds strange to me. Any way you could link to the clips or 10 or 20 seconds of them so I could download them and fool with them a bit? I've seen things like this when recording different instruments - ie the plots will look different but the instruments will seem to have the same loudness.Perceived loudness doesn't necessarily correlate with peak volume, but if all the mics were recording pretty much the same material with consistent settings I don't have any ready explanation.

January 3rd, 2011, 12:12 PM	#9
Rick Reineke Inner Circle Join Date: Aug 2008 Location: New York Posts: 2,039	I can see by the screen-shot of Vegas, there's at least one audio plug-in assigned to each channel. Though it does not alter the visual waveform, If you up render and upload the audio, delete the plug-ins beforehand. Off topic: The screen-shot of Vegas was most likely the 'default' plug-in chain: Compressor, Gate and whatever the third default plug-in was that SCS deemed 'necessary' for every track and 'one size fits all'. I would advise any Vegas user to remove the audio plug-ins and change the default. Add plug-ins only when necessary.

January 3rd, 2011, 02:08 PM	#10
Harry Simpson Major Player Join Date: Aug 2009 Location: Nashville, TN. Posts: 581	Jim Do you have Vegas Movie Studio or should I just save a sample of each off to .wav file and send to you? The full audio track for each has me talking at 90, 80, 70, and 60 levels. And yes these are the default FX applied to every sound and I'll remove them from defaults and before saving off to .WAV files. Jim I'll save off to .WAVs and name them appropriately and send as an attachment to email - think i still have your email. Thanks Harry __________________ Nashville TN using Canon 5D MK3, Canon 550D, RODE SVM mic, 70-200 f2.8L II IS, 24-105 f4L IS, 50 and 85 f/1.8, Vegas Pro 11, Zoom H4n, Blackbird, Lilliput Monitor, Lightroom

January 3rd, 2011, 06:30 PM	#11
Jim Andrada Inner Circle Join Date: Feb 2007 Location: Tucson AZ Posts: 2,211	Great - I have the full Vegas /Sound Forge combo but .wav would be fine