Rendering wav from different DAW in reaper with no edits and the file is smaller

m5blackmond · 08-17-2022, 12:03 PM

Hello! Hope my title makes sense.

I have a wav file that was rendered at 32 bit from a different DAW (pretty sure it was pro tools).

I imported this into reaper and then just rendered it as is (configured sample rate to 44100, WAV bit depth to 32 bit FP, unchecked "tail". Everything else default).

If I look at the file in my file explorer, the input file and output file still have the same bit rate (2822 kbps). but the new file is a couple hundred kb less. E.g.

Input file: 68736 KB
Output file: 68463 KB

From what I can tell, the audio sounds the same. I can't tell the difference, but I'm not an audiophile, so I may just not be able to hear it.

My concerning question is -- did I lose any quality here?

Secondarily, if I'm not losing quality, what am I losing? Does pro tools maybe embed some meta data or header information that is getting stripped by reaper?

I looked at the details of both files, and there's no difference in meta data, but one difference was there is a field called "attribute", and it was =A (archived) in the output file, and =N (no attributes) in the input file. Maybe it's related to this?

Finally, is there some sort of tool I could use to verify this?

schwa · 08-17-2022, 12:07 PM

If the files have the same length, sample rate, and bit depth, the size of the data will be identical. The difference might be metadata that doesn't affect playback (something like file recorded time or the specifications of the DAW itself), or it might be that both DAWs are embedding metadata but the other application is embedding the same metadata in multiple formats.

Different kinds of metadata won't necessarily show up in the system file explorer, but if you drag the file that was recorded in the other application into REAPER and open the media source properties, it will list any metadata chunks that are not recognized.

Fabian · 08-17-2022, 12:08 PM

Quote:

Originally Posted by m5blackmond

Finally, is there some sort of tool I could use to verify this?

With "this" I suppose you mean whether the two files are identical or not.

You could do a null test.

Create a new project in Reaper. Load both files on separate tracks with their beginnings lining up. Invert the polarity of one and hit play, You should get absolute silence. If you do not get absolute silence, then the files are not bit-identical.

m5blackmond · 08-17-2022, 12:17 PM

Quote:

Originally Posted by Fabian

With "this" I suppose you mean whether the two files are identical or not.

You could do a null test.

Create a new project in Reaper. Load both files on separate tracks with their beginnings lining up. Invert the polarity of one and hit play, You should get absolute silence. If you do not get absolute silence, then the files are not bit-identical.

Wow this is a neat trick! I just tried it and it was silent so I think I'm good. Appreciate that tip.

Quote:

Originally Posted by schwa

If the files have the same length, sample rate, and bit depth, the size of the data will be identical. The difference might be metadata that doesn't affect playback (something like file recorded time or the specifications of the DAW itself), or it might be that both DAWs are embedding metadata but the other application is embedding the same metadata in multiple formats.

Different kinds of metadata won't necessarily show up in the system file explorer, but if you drag the file that was recorded in the other application into REAPER and open the media source properties, it will list any metadata chunks that are not recognized.

Great info. Thank you!

schwa · 08-17-2022, 12:21 PM

If you want (I'm kind of curious), you could send us the file at support at cockos and I can let you know what the extra data is.

m5blackmond · 08-17-2022, 12:30 PM

Quote:

Originally Posted by schwa

If you want (I'm kind of curious), you could send us the file at support at cockos and I can let you know what the extra data is.

I'd be more than happy to do that! It's not clear to me where you're asking me to upload them. Is there another forum for support or was that an email?

schwa · 08-17-2022, 12:39 PM

It's an email. You can also post it somewhere and link to it here if you prefer.

m5blackmond · 08-17-2022, 03:53 PM

Quote:

Originally Posted by schwa

It's an email. You can also post it somewhere and link to it here if you prefer.

Gotchya. I just sent it to the email. Thanks again

schwa · 08-17-2022, 03:58 PM

Thanks for sending the files. The longer file has 274k of embedded metadata, almost all of which is proprietary Pro Tools information.

Wav files, like most audio files, are containers that can hold all kinds of stuff in addition to the audio data. There could be an embedded image or icons in there or who knows what. Regardless, it doesn't affect playback in any way.

m5blackmond · 08-17-2022, 04:52 PM

Quote:

Originally Posted by schwa

Thanks for sending the files. The longer file has 274k of embedded metadata, almost all of which is proprietary Pro Tools information.

Wav files, like most audio files, are containers that can hold all kinds of stuff in addition to the audio data. There could be an embedded image or icons in there or who knows what. Regardless, it doesn't affect playback in any way.

Thanks a lot for taking a look at that. That gives me some piece of mind that I'm not compromising my songs!