Very good question Laurence - I've been going through and checking just about every variable in this process, and ... I'll confirm this in half an hour after rendering, but I may have discovered that I have been doing Handbrake an injustice, and that it could be that it's the Avid DNxHD step that has been doing the damage!

Because it's an Intermediate format I had assumed that the audio was uncompressed, but I've just found that the template had an audio format called English (QDM2) (QDesignMusic2).

I'm currently rendering with uncompressed audio, and once this one has passed through Handbrake I'll report back with a slice or three of humble pie...

Well that was it - what a relief! Sorry, Handbrake, it wasn't you, it was the DNxHD template.

The uncompressed audio version came through Handbrake unscathed and is on its way to the client via ftp.

When the previous discussion covered this subject, I stayed a little quiet and I shouldn't have. I guess I didn't want to be the only one who couldn't see the emperor's new clothes ;-)

For anyone looking at this in the future:

1/ Uncompressed audio in DNxHD
2/ Make sure that Vegas sample rate conversion is set to best (it defaults at "good" which is not).
3/ Make sure that Handbrake is not doing a sample rate conversion (set it to the same sample rate as your Vegas render), and that the format's match (Handbrake wants to do a surround to Dolby Pro Logic downmix unless you tell it not to).

There is a new AAC encoder available in Handbrake nightly builds, ffmpeg aac. I haven't tested it to see how much better it is than faac, which has a less than stellar reputation at lower bitrates..The nightlies also have much better support for DNxHD in general.

https://build.handbrake.fr/view/Nightlies/job/Windows/

Although not helpful for those of us sending PCM in DNxHD, there are several "passthrough" (smart render) options for AC3 and DTS, also a Lame MP3 encoder, which is really nonstandard for MP4 video but sounds great.

Remuxing the finished audio with the original is also possible, and something I've done from time to time.

@ Peter Wright,

PCM audio in DNxHD is one of those little things I took for granted (and shouldn't!)
Completely slipped my mind when you asked in another thread recently.
I'm going to put an annotation on the Youtube tutorial to address that.

How do you get DNxHD to pass through surround? I keep getting errors when I try to render more than 2 audio tracks. I've tried various templates ie uncompressed, 32 bit float, 24 bit, etc.

My project is 24 bit/48 kHz surround.

rocky

bastinado,
Render a separate 5.1 AC3 audio file and mux that when you're all done in Handbrake.
[EDIT] I ran some tests.
You can do this in MKVMerge (outputs MKV)
You can do this in TSMuxer (outputs TS)
You can do this in AviDemux (outputs MP4) but you have to wade through some messages.

Not that MP4 with AC3 audio may not play in all devices.

Laurence,
I'd like to add your excellent audio instructions to the Description pane on Youtube, with proper credit of course.

The audio workflow was something I overlooked when making the tutorial, because mine has become almost subconscious over time. It will be covered in the next tutorial version.

musicvid, do you have a youtube channel or can you send a link to any tutorials you have done?

Youtube channel is here:
http://www.youtube.com/user/musicvid10?feature=guide

Jerry's excellent project page is here:
http://www.jazzythedog.com/testing/DNxHD/HD-Guide.aspx

MusicVid, HB appears to accept 6 channel input and will encode it as 6 channel AAC. Is there a way to get it to do this?
thanks,
rocky

"MusicVid, HB appears to accept 6 channel input and will encode it as 6 channel AAC. Is there a way to get it to do this?"

Not from DNxHD + 5.1 audio file because Handbrake is not a muxer ;?(
Also, I have not found a way to encode 5.1 AAC in Vegas.

So if you're brave, I think AviSynth / MeGUI already has the combination of capabilities you're after. Maybe Nick Hope can jump in here after his connectivity is restored and enlighten us all.

I think these formats will talk to each other better in the future; Handbrake developers are definitely keeping us on their radar, based on a couple of recent developments.

I'll run one more experiment to see if I can remux DNxHD with 6 Ch discrete PCM from Vegas, then encode as 5.1 AAC in Handbrake, but based on past experience, I am not holding my breath. Handbrake pretty much gives PCM a blank stare . . .
;?)

[EDIT] I've posted the question to Handbrake developers on their forum. Will get back with responses here.

So if you're brave, I think AviSynth / MeGUI already has the combination of capabilities you're after. Maybe Nick Hope can jump in here after his connectivity is restored and enlighten us all.

It looks like the capability is there in MeGUI and the NeroAAC encoder, but I've personally never done anything more than stereo. Guidance on my Vegas > web workflow is here.

"Laurence, I'd like to add your excellent audio instructions to the Description pane on Youtube, with proper credit of course."In the spirit of "It's always better to ask for forgiveness rather than permission", I'll also put this on our project page. http://www.jazzythedog.com/testing/dnxhd/hd-guide.aspxhttp://www.jazzythedog.com/testing/dnxhd/hd-guide.aspx[/link]

Email me or post back here if this is an issue.

...Jerry

>"Laurence, I'd like to add your excellent audio instructions to the Description pane on Youtube, with proper credit of course."

You guys are making me blush...yeah, if I said something worthwhile, repost away. Credit me if you want but it isn't neccessary.

Here's an answer from Rodeo, a developer at Handbrake. It's good news, but obviously still a WIP. I'll work on some muxing options at the end of the week. I still have a feeling adding 5.1 AC3 after Handbrake is a better option for now, if your device will play it. Anyone know if we can encode 5.1 AAC directly in newer versions of Vegas?

Whoops! I got my extensions mixed up.

...Jerry

So on a PC, which is better audio quality wise for a give bitrate, Libav or Lame mp3? I'm just uploading to Vimeo so I don't care about it being non-standard.