Half of Waveform Showing

[BobbyT]

When I drag a mono WAV file into Logic (10.7.8) only the top half of the waveform shows. When I enlarge the track as much as possible, the full waveform appears.  Any ideas why this is happening?

Thank you. 

[David Nahmani]

It sounds like you may have recorded only one channel of a stereo recording? That would look like the images below (two images at different vertical zoom level values):  

Is that what you're seeing?  

[BobbyT]

Thanks for writing. No, I didn't record one channel on a stereo track. This is happening across multiple tracks with various instruments (kicks, vocals, etc). I attached 2 images. The first image shows a mono file dragged into the Workspace. The second image is the same file enlarged. 

Why does just the top of the waveform appear, but also why does it fully appear when enlarged?

This track was recorded on a different DAW and is MONO.

Thanks

Edited November 18, 2023 by BobbyT

[David Nahmani]

Can you attach that recording here? I'll have a look. 

[Jordi Torres]

Hi guys,

That looks like an asymmetric waveform.

Here’s some info on that phenomenon:

https://producenewmedia.com/asymmetric-waveforms-should-you-be-concerned

https://www.soundonsound.com/sound-advice/q-why-do-waveforms-sometimes-look-lop-sided?amp

J.

[BobbyT]

Hi David. The file is attached. Thank you. K IMPALA.aif

[BobbyT]

Thank you Jordi. This instance is peculiar because the waveform begins with the top half but changes and appears in full once the track is widened by 75% or so. 

[BobbyT]

Update: When I export the track to the desktop then drag it back in, the whole waveform appears properly. 

[David Nahmani]

It's odd, I can't reproduce this issue at all here, no matter what zoom level I choose I always see the whole waveform. 

[Jordi Torres]

I’m away from my computer, but after David’s test I would also like to give that file a try and see what I get here.

J.

[Jordi Torres]

1 hour ago, David Nahmani said:

It's odd, I can't reproduce this issue at all here, no matter what zoom level I choose I always see the whole waveform. 

I also can't reproduce the issue here:

J.

[BobbyT]

Thanks Jordi and David. 

The original file I uploaded yesterday was too large. So I uploaded an excerpt from it, edited and exported in Logic. Once I dragged that file back in, like you, it was okay. Today I attached a smaller version that was exported the same way as the original file. This one has the same issue once dragged into Logic. Thank you.

Edited November 20, 2023 by BobbyT

[fuzzfilth]

Imports just fine here.

Though his will not explain the source of the problem, I bet that if you 2-click the original Region in Logic, click File (not Track), then select Audio File>Refresh Overview(s), it will show up correctly.

[David Nahmani]

I can reproduce the issue! And refreshing overviews does not help. In fact the waveform looks wrong in the Tracks area and in the Track editor, but looks fine in the File editor. 

Weird! First time I see this.

[BobbyT]

I think the type of file or recording, exporting issue, etc. can be ruled out as the waveform is there but not displayed.

I installed 10.8, so the version is not an issue as the problem occurs in both 10.8 and below. 

Edited November 20, 2023 by BobbyT

[BobbyT]

Bounce In Place displays the full waveform on a new track. 

[David Nahmani]

2 hours ago, BobbyT said:

Bounce In Place displays the full waveform on a new track. 

Yes, same here, so I can't explain it. 

[BobbyT]

So strange. I suppose BIP is my best option for now. Hopefully there isn't any audio compromises or changes. Thanks for looking into it. 

[David Nahmani]

3 minutes ago, BobbyT said:

So strange. I suppose BIP is my best option for now. Hopefully there isn't any audio compromises or changes.

Or export, rather than BIP? 

Or you could even try to Control-click the region and choose Convert > Convert to New Audio File? 

[BobbyT]

As I am new to Logic, is there a benefit to exporting or converting to new audio file v. BIP? Does BIP affect the sound quality, etc? I have yet to fully explore BIP, exporting etc?

Edited November 21, 2023 by BobbyT

[David Nahmani]

BIP requires many conditions to make sure it does not affect the audio data whereas converting requires none. So I would recommend you start by trying to convert. 

[BobbyT]

Ahh, okay. Good to know. Thank you

[David Nahmani]

You're welcome. 🙂 

[BobbyT]

Looks as if Convert Audio and Export are not working either. 

Edited November 21, 2023 by BobbyT

[David Nahmani]

Just now, BobbyT said:

Looks as if Convert Audio is not working either. 

Ugh..

Ok so I tried a few things and apparently the best way to fix it is bounce in place. Use the following settings to make sure you don't change the audio data:

[BobbyT]

Okay. Will do. Thank you. 

This same file was uploaded into ProTools and Digital Performer and the waveform is fine. 

[Jordi Torres]

@BobbyT, for what it's worth, I could not reproduce the issue with the second file you uploaded in Logic 10.6.3 (which is the latest version I have at my disposal at the moment).

I did a bit more digging and it may be that there's some data in that file that this version of Logic just ignores and that with newer versions of Logic produces this phenomenon. That explains why generating a new version of the file (BIP, etc.) from within Logic, which apparently strips this additional data, takes care of the problem.

The file comes from Digital Performer and there is some metadata chunks that both the Python SciPy library and BWF MetaEdit complain about.

J.

Edited November 21, 2023 by Jordi Torres

[BobbyT]

Thank you Jordi. Will the stripping away of info adjust the sound at all?

Many of the files, which were all exported out of DP, have this half wave issue and some don't. I wonder why that might be.

Edited November 21, 2023 by BobbyT

[Jordi Torres]

23 minutes ago, BobbyT said:

Thank you Jordi. Will the stripping away of info adjust the sound at all?

If you follow @David Nahmani's advice the actual audio data should not be affected, those meta data chunks are themselves separate from the audio data, so removing them should not make any difference to the sound.

Unfortunately I could not find much info about the ones that start with "dp" (dpam, dprn, dpte), but I think we can assume those come from DP.

"LGWV" is actually "Logic Wave", "rgne" apparently comes from Pro Tools, and "acid" is an ACID Loop chunk.

23 minutes ago, BobbyT said:

Many of the files, which were all exported out of DP, have this half wave issue and some don't. I wonder why that might be.

Would be good to compare the ones that do and the ones that don't.

J.

 

Edited November 21, 2023 by Jordi Torres

[BobbyT]

@David Nahmani Thank you David and Jordi. @Jordi Torres I can upload a file (that shows a full waveform) from the same session. Let me know if you'd like to compare. 

Update: Clicking on the region then choosing 1 REGION AS AUDIO FILE and exporting works. Not sure yet what 1 Region as Audio File does to audio and if it is preferable to BIP in this instance. Thank you

Edited November 22, 2023 by BobbyT