Export 24/96 to MP3?

I tried rendering a 5.1 surround 24/96 montage to surround MP3 and got half-speed audio. I’m guessing the converter doesn’t like 96kHz, but then I’m not sure if this is a WaveLab thing or an MP3 codec thing. I haven’t found anything definitive saying MP3 encoders require 48k or less. Is it necessary to do an intermediate render to 48k? No dither, I assume?

Any advice is appreciated.

You got a 5.1 MP3? I could only make a 5.1 MP3 that indicates as Stereo in iTunes and VLC, not 5.1. And using 48k only.

However, Wavelab AAC 96K 5.1 seems fine in iTunes and VLC, and indicates multichannel.

But Wavelab FLAC 5.1 “seems” to be Stereo too, not 5.1, according to VLC.

I couldn’t get any of them to loadback in Wavelab using insert Surround File.

What program did you use to check the 5.1 MP3?

I’ve never tried this before, so I’m sure PG will be a lot more help with this than I am. That’s as far as I got. I still wonder why I can’t get 5.1 MP3 or 5.1 FLAC correctly in Wavelab. Seems like it should work.

Instead of using MP3, I suggest using a customized iTunes Plus format. Please read this document:

Then type “afconvert -h” in terminal to study its parameters.

Not at all. It’s stereo. I didn’t even notice the channel count when I first heard it slogging along at half speed. For the record, I checked it in VLC and Windows Media Player. After your post, I verified the (stereo) channel count in Cubase Pro 9.

As it turns out, reducing the resolution does indeed fix the audio speed but still doesn’t produce a surround MP3. I’ve tried a half-dozen configurations of the Fraunhofer and LAME encoders in WaveLab without luck. It’s always stereo (and with the center channel panned hard left, so there’s no thoughtful downmixing at work).

What did work was exporting a 32-bit float multi-channel WAV to Cubase. Cubase exported to 5.1 MP3 surround without a hiccup. Of course, command-line LAME is also an option. I might just do up a batch file once I figure out my workflow and ideal LAME parameters. Then again, it remains to be seen if the Fraunhofer encoder sounds better or worse than LAME. My only experience is with LAME, but I’ve heard Fraunhofer can do better work on certain types of content.

Woops! Scratch that. Looks like LAME doesn’t support multichannel audio after all. So, Cubase appears to be my only solution.

It’s interesting that WaveLab clarifies LAME’s options as Mono, Stereo, or Dual Mono. It’s another reason to believe that the Fraunhofer encoder is supposed to support multichannel. I suppose it’s worth a bug report.

Woops again! Still no place to submit WaveLab bug reports?! Grrr…

Did you try inserting the WaveLab Resampler to 48k, in the chain?

That makes no difference here PG. Even rendering from a 44.1 5.1 file, FLAC and FH MP3 5.1 render files appear as Stereo in VLC. I don’t know about the MP3, but the FLAC conversion should definitely work because it works in other programs, and those files appear fine (as 5.1) in VLC. But the Wavelab FLACs don’t.

But the Fraunhofer AAC 5.1 seems to work fine at 96, 48, and 44.1.

Note that “MP3 Surround” is not part of any MP3 standard. It is a later extension by Fraunhofer & friends that is supported by some other companies, and not by Lame (because it’s proprietary). For fully compatible surround, you’re better going with AAC or AC3.

Paul

I can export from WaveLab 96k 5.1 (montage) sur surround 5.1 48k mp3. But only Audition can read the file properly…

Thanks for that Paul. That’s sort of what I found, that Fraunhofer put it out more than 10 years ago, but seemed to drop support and moved on to AAC.

It seems like the practical options for comparison of lossy 5.1 are probably:

Fraunhofer codec AAC 5.1 (in Wavelab)
Apple codec AAC 5.1 (on Mac, as ShikiSuen suggested above)
Apple codec AAC 5.1 (on Windows, with QAAC plugin in Foobar2000)
Dolby AC3 (in MediaHuman Audio Converter and others)

Maybe there are others.

That raises an important question: I was hoping to publish these on my website, using the standard Wordpress audio player and shortcodes. But it only supports MP3, M4A, OGG, and WAV files. But now, if you’re suggesting there’s little chance anybody’s web browsers will support MP3 surround - something I hadn’t considered - and it’s just gonna confuse and frustrate my visitors, then why bother? I might as well just offer file downloads instead.

Try the Wavelab AAC (M4A), or even Wavelab OGG. Those should work in your Wordpress player I think.

If you want a comparison of the Wavelab Fraunhofer AAC to Apple AAC, use the suggestions in my earlier post.

Will do. Thanks a million!

PG, the Wavelab FLAC surround (and now Wavelab Ogg surround too), don’t seem right. In VLC, Foobar, and MediaHuman the Wavelab files are identified as 2 channel.

FLAC and Ogg surround files made in Foobar and MediaHuman from the same WAV surround file are fine in all 3 programs, so there really seems something wrong with the Wavelab FLAC and Ogg surrounds.

However the Wavelab AAC surround is fine in everything.

there really seems something wrong with the Wavelab FLAC and Ogg surrounds

I can believe that, as it was never said to be supported so far…

Philippe

Not supported by whom? WaveLab or Ogg?

Paul

WaveLab

I think Wavelab should support FLAC 5.1 multichannel files and Ogg 5.1 multichannel files render and open. The free programs I mentioned do. Reaper does. I believe Cubase and Nuendo do.