Audio re-render to higher bit rate - 96 kbps to 192 kbps-split stereo

Sam-Stalos wrote on 12/7/2023, 3:51 PM

I want to render an audio track to a different bit rate and need to know if my Vegas 20 Pro is performing correctly or if my expectations are incorrect.

I am working with a single mono track that contains only voice narration. The file is mp3 format and has a bit rate of 96 kbps. I want to re-render that track to 192 kbps, mono format. The increased size (length) of the new file is not of concern.

When I open my Vegas Pro 20 Render Menu for this audio track, the Bit Rate window defaults to 8 kbps. I can open that Bit Rate drop-down menu and adjust the bit rate to no higher than 122 kbps. However, by selecting the “Split Stereo” option, I can adjust the bit rate to 192 kbps. The problem is, the client can accept only mono, and I’d like to eliminate the extra step. Should I take the “split stereo” track and re-render it to mono, which seems like a strange way to achieve a mono conversion. And doesn’t all of this re-rendering encourage the appearance of unwanted artifacts?

And finally, what command in Vegas 20 do I use to verify the specs of an audio file (in terms of bit rate, sampling rate and bit depth) that I have loaded on an audio track?

Comments

bvideo wrote on 12/7/2023, 5:04 PM

In vegas, you can see some essential properties of an audio or a video event by right clicking and selecting "properties" and then choosing the [media] tab. More extensive properties can be found with the 3rd party mediainfo software. Maybe someone else is more familiar with how to use Vegas to refactor your audio to the degree you would like.

mark-y wrote on 12/7/2023, 5:06 PM

1. Resampling a 96Kbps mono mp3 to 192Kbps mono pcm will accomplish, . . . absolutely nothing except to add air. You will still have 96 gallons of water in a 192 gallon barrel, = half full. No aspect of the audio will be restored or enhanced by increasing the sample rate or bit depth, and you may get slight additional Quantization, Delay, and Harmonic noise.

With newer restoration and AI algorithms, a certain amount of perceived "alchemy' is now possible. Check out iZotope RX11 and Adobe Audition, to name a couple. A scaled-back version of iZotope is included in some Vegas and Sound Forge packages.

Keep in mind that 96Kbps mono is the equivalent of 192Kbps stereo, the way total bitrate is commonly reported.

@rraud may have additional thoughts for you.

2. The means of accessing Audio file properties in Vegas is the same as for video:

https://www.vegascreativesoftware.info/us/forum/faq-how-to-post-mediainfo-and-vegas-pro-file-properties--104561/

Sam-Stalos wrote on 12/7/2023, 6:52 PM

Thank you both for your responses. My problem at this point is not really maintaining the audio quality of the original mp3 96 kbps file, but rather satisfying the client's requirement for a mono file that reads 192 kbps when the original file was recorded at 96 kbps. I just tried to re-render the "split stereo" 192 kbps mp3 file to mono using Vegas 20, but even with the split-stereo 192 kbps file loaded, as verified with the right-click Properties command, when I tried to re-render to mono, Vegas 20 would only allow a maximum of 128 kbps at 44.1 kHhz for the mono version.

I have a copy of Vegas 9 and will see if that is of any help.

 

john_dennis wrote on 12/7/2023, 7:53 PM

@Sam-Stalos

I once worked in a branch office where the branch manager was named Ted. When I was a staff manager, I would often get requests that made no sense at all to anyone from Earth, but, I went about doing it because they paid me...

... well.

We had an in-group phrase to describe that kind of nonsense, a TWI. Ted Wants It.

This is how I would satisfy the TWI that you described.

I hope you're being paid ...

... well.

Sincerely,

Howie Duit

Sam-Stalos wrote on 12/7/2023, 9:35 PM

Hi John and/or Howie,

So if I understand correctly, you rendered to a .wav file and then, using a program called Shutter Encoder, you were able to produce a mono file at 192 kbps. Do I have that correct?

RogerS wrote on 12/7/2023, 10:19 PM

That appears to be correct and hilarious.

john_dennis wrote on 12/7/2023, 10:54 PM

That’s correct.

rraud wrote on 12/8/2023, 11:24 AM

Vegas 20 would only allow a maximum of 128 kbps at 44.1 kHhz for the mono version.

Did you open the 192 kbps preset and choose, "Customize Template", which should have the 'Mono' checkbox option for 192 kbps MP3s.. I do not have Vegas 20 but I checked Vegas 9, 16 and 21 and they do.

btw, welcome to the Vegas Pro users community @Sam-Stalos.

Sam-Stalos wrote on 12/8/2023, 12:07 PM

Hi John,

A case of Rothschild's finest is on its way. Thanks again.

Sam-Stalos wrote on 12/8/2023, 12:11 PM

Hi Rraud,

Yes, I opened the "Customize Template" and it did show the Mono check, which in Vegas 20, automatically defaulted to a bit rate selection of which 192 was not an option for mono. Hence the problem.

rraud wrote on 12/8/2023, 3:23 PM

Sorry @Sam-Stalos. I misunderstood and was looking at a different encoder.. DUH. Unfortunately that is a limitation in Vegas. A work-a-round is to render the Vegas audio mix as a PCM Wave file and encode the MP3 from the PCM master in Sound Forge (14 thru 17, which supports 192 kbs and higher mono encoding). WinLAME RC3 also supports mono encoding in all resolutions.

Sam-Stalos wrote on 12/8/2023, 6:01 PM

I found another solution: Audacity version 3.4.2. No need to bump up to .wav. It will save the 96 kbps file as a constant bit rate 192 kbps file and keep it mono.

rraud wrote on 12/9/2023, 12:08 PM

From a quality standpoint, re-encoding an MP3 is not recommended (even to a higher bps), but if it floats the boat for you and the client...