Exporting B format cannot be read by other ambisonic player apps

[Ambience]

I've been using both ATK and IEM (separately) and it appears when I render a 4 channel file and open it in the Zoom Ambisonic Player to test it the format says "unknown". I'm wondering what I'm doing wrong.

Reaper is set up as follows:

Master with 4 track channels
4 mono tracks - each using 4 track channels
1 Folder track - using 4 track channels, it receives tracks 2/3/4/5. Under the audio section of the receives it goes Audio: 1>1, 2>2, 3>3, 4>4

The folder track has ATK FOA Encode AtoB. The sub tracks then have my tweaks with Planewave. When I render the file with the AtoB encoder still selected and using 4 channels on the render options, I import the new file into Zoom Ambisonics Player to test it but it says "unknown format".

Also I noted that when I have the ATK A-B encoder active the audio sounds very nicely separated in my headphones but when I enable the binaural decode the audio almost sounds as if it degrades slightly and the details in my right here seem to get flipped to my left ear.

Appreciate any help!

[plush2]

Originally Posted by Ambience

I've been using both ATK and IEM (separately) and it appears when I render a 4 channel file and open it in the Zoom Ambisonic Player to test it the format says "unknown". I'm wondering what I'm doing wrong.

Reaper is set up as follows:

Master with 4 track channels
4 mono tracks - each using 4 track channels
1 Folder track - using 4 track channels, it receives tracks 2/3/4/5. Under the audio section of the receives it goes Audio: 1>1, 2>2, 3>3, 4>4

The folder track has ATK FOA Encode AtoB. The sub tracks then have my tweaks with Planewave. When I render the file with the AtoB encoder still selected and using 4 channels on the render options, I import the new file into Zoom Ambisonics Player to test it but it says "unknown format".

The "unknown format" error makes me suspect the filetype you are rendering to. Is it WAV? MP3? OGG?

Your routing all seems correct based on your description.

Also I noted that when I have the ATK A-B encoder active the audio sounds very nicely separated in my headphones but when I enable the binaural decode the audio almost sounds as if it degrades slightly and the details in my right here seem to get flipped to my left ear.

Appreciate any help!

If you are listening without any speaker decode then it should sound basically like listening to a mid-side recording without decode. When you say it is flipped from your left ear to your right is that based on anything you know about the original spatial placement of elements in the recording or just based on how it sounded before you turned on binaural decode?

[Ambience]

It's a standard wav file, I've attached a screenshot of my render settings and also a project template, hopefully it loads the ATK plugins for you also.

The flipping of sound is based on how it sounded before turning on the binaural decode plugin. I'll try downing the SPARTA plugins and see if it happens with them.

Thanks for the reply.

[plush2]

The first problem I see is that you have each track routed to the Ambisonic Mix track via a send and also routed via "Parent send channels from/to" (a checkbox at the top of each routing page). You are sending 1-4 from each track via that parent routing and then 1, 2, 3, 4 respectively via the sends.

Are you mixing 4 mono sources together and panning them into a b-format ambisonic soundfield? That is how you have it set up except each track output should be 1-4 rather than 1, 2, 3, 4 respectively as it is now. Each of those ATK Planewave plugins is panning a mono signal into a full b-format 4 channel soundfield. Each of those needs to be mixed together to create your final 4 channel ambisonic soundfield mix. So to do this get rid of the individual sends to Ambisonic Mix on each track.

If you are mixing an existing a-format first order ambisonic recording (4channels) then you don't need the ATK Planewave on each track, each track can be mono and your routing should be (on either the top "Parent send channels from/to" or in the sends to Ambisonic Mix) 1 -> 1, 1 -> 2, 1 -> 3, 1 -> 4, respectively. This is because each source is mono and therefore playing back to channel 1 on each track.

Simpler still, if the recording is a 4 channel file you can just drag that onto a new track which will automatically set to 4 channels.

I would guess the unknown file type error in the player might be because it doesn't support 96 kHz sample rate.?

[Ambience]

In terms of the Zoom Player, it could be possible that it will not accept anything other than a file made on a zoom device as I've tried all different samples rates and resolutions etc.

I am mixing 4 mono sources and If I am understanding you correctly, I just have to remove the folder receives otherwise I am essentially sending the same thing twice? Also when you say about having to mix together each mono track, do you mean creating a render out of the DAW?

*ignore the non ATK plugins in the wire diagram.

[plush2]

Originally Posted by Ambience

I am mixing 4 mono sources and If I am understanding you correctly, I just have to remove the folder receives otherwise I am essentially sending the same thing twice? Also when you say about having to mix together each mono track, do you mean creating a render out of the DAW?

*ignore the non ATK plugins in the wire diagram.

I think you've got it now. Basically those mono tracks each become a 4 channel element (with the W, X, Y, Z first order components) of your final mix. If you match up those 4 channels from each of those tracks (much like you would Left and Right in a stereo mix) you will get your finished first order ambisonic mix.

[Ambience]

Got it, and thanks for taking time to explain, really appreciate it!

Edit: It would appear that the render options do not offer any type of metadata to help other ambisonic apps to indentify that it's dealing with an ambisonic file. I'll have to look for a way to add this metadata.

[Kewl]

Originally Posted by Ambience

In terms of the Zoom Player, it could be possible that it will not accept anything other than a file made on a zoom device as I've tried all different samples rates and resolutions etc.

The Zoom player expects the Zoom H3-VR metadata in the wave file. If you really want to use the Zoom player, you can copy/paste relevant metadata (A or B format, etc) from a H3-VR file to a generic wave file using BWF MetaEdit. I have done it a few times.

https://mediaarea.net/BWFMetaEdit

That being said, if you already use Reaper, I would suggest you create a RPP dedicated to playing back ambisonic files. You can specify a much better decoder with IEM AllRADecoder than the one in the Zoom player.

[plush2]

Originally Posted by Kewl

That being said, if you already use Reaper, I would suggest you create a RPP dedicated to playing back ambisonic files. You can specify a much better decoder with IEM AllRADecoder than with the one in the Zoom player.

That is what I was thinking as well. The Zoom player is really designed as an entry point for users who come at ambisonics from zoom gear specifically. Like Kewl says, you'll get better results and more flexibility by monitoring your work in Reaper directly.