Te max bit rate for MP3 files is 320kbs, however AAC audio files can be encoded even higher, but that is usually not necessary. I think the suggested default is 192kps which is too low IMO for music programs.

YouTube re-encodes A/V submissions and allegedly lowers the loudness if it exceeds -14 LUFS (integrated). You can check projected loudness 'penalty' change at: https://www.loudnesspenalty.com. You will need to create an audio only file though.

btw, do not confuse the loudness scale (LU or KU) with dBFS peak, RMS, VU or others.

@T-B-edits The audio tab in project properties only controls the internal storage depth of audio data inside Vegas and on it's audio mixing buses. Setting it to 24 makes the biggest difference if you have 24-bit pcm audio tracks in your project. AAC tracks on video clips are inherently 16-bit so the difference would be minimal unless you mix audio from multiple clips. Not sure if that sample rate even applies to AAC. I generally record audio for video on a flash recorder at 24-bit 48k pcm (wav) and set the project audio to that, even if I render a video with aac audio set to 384k in the render template. Keep in mind that the 384k aac bitrate is a sample rate before compression that comes down to a much lower bit-rate in the file after size-compression, which leaves stuff out that you might not notice. And that aac size compression does not necessarily affect loudness, which is raised by compressing dynamics as opposed to reduce the size of the clip. Dynamics compression is a form of automated gain-riding akin to raising the volume during quiet parts and/or lowering it on loud parts so that the overall volume can be raised without overloading.

The Intel QSV templates support a limited number of format settings: 320 Kbps AAC may not be among them, even though it appears in the dropdown menu.

The Mainconcept rendering option will encode 320 Kbps AAC audio. I suggest keeping the sample rate at 48 Khz, which is the normal sampling rate for video with audio.

The Intel QSV templates support a limited number of format settings: 320 Kbps AAC may not be among them, even though it appears in the dropdown menu.

The Mainconcept rendering option will encode 320 Kbps AAC audio. I suggest keeping the sample rate at 48 Khz, which is the normal sampling rate for video with audio.

@Musicvid On my screen I do not get option of the dropdown menu. I tried to pull this out wider, scroll down, and uncheck include video. What else could I try to do to access the full menu? included a photo of what I see! Thanks for the help and feedback

@Dexcon for some reason looks like my dropdown menu is cut off? I tried to pull this out wider and scrolling down, what else could I try to access the full screen or to change this setting? Thanks for your feedback!

@Howard-Vigorita Interesting info, thank you for taking the time to explain! How would you recommend to set my render settings to get an audio render that is most true to the orignal song file? The project is a music video

You guys both need lower your Windows font scaling in order to access the tabs and such at the bottom. I recommend not going above 125%, but your screen resolution also figures into this.

There are also these settings in Preferences, which work fine for me at their defaults.

@Musicvid where do I go to lower font scaling? I searched in my computer's settings for that and anything related but it says I have it on the lowest option. Is there anywhere to do this in Vegas?

Also if you wouldn't mind, please elborate on the two bottom settings, is that to lower font size or something else?

Thanks

where do I go to lower font scaling?

You need to ask the internet, since OS versions are different.

Also if you wouldn't mind, please elborate on the two bottom settings, 

The tabs at the bottom are "Audio," "System," and "Project."

When it looks like this, you are seeing the complete window.