Understanding More About B Format Measurements and CATT ReflPhinder

[Trdat]

Imagine being one of those people who can spend hundreds of dollars on a whim!

Interesting, thank you for sharing!

I installed it, but since I don't have any Ambisonic recordings to try it our with, I don't know how it would show reflections. I didn't see a Z axis... but that may be visible if it has a file loaded.

If I happen to get to the Zoom V3 before you I'll send a file across.

 

[No. 5]

Well that's very kind of you, thank you! And I will do the same.

 

[Trdat]

Imagine being one of those people who can spend hundreds of dollars on a whim!

Interesting, thank you for sharing!

I installed it, but since I don't have any Ambisonic recordings to try it our with, I don't know how it would show reflections. I didn't see a Z axis... but that may be visible if it has a file loaded.

I just purchased the Zoom V3 but reluctant to spend more on Refphinder. Once I get it and work out how to use it I will send you a recording and hopefully that free software I linked you in will be good enough to detect from where the reflections are coming from.

I also have some basic insturctions from Angelo on how to find spectral content of reflection from another software but I can't make anything from it. I will send it to you with the recording and maybe you can work it out.

Will keep you updated.

 

[No. 5]

I just purchased the Zoom V3 but reluctant to spend more on Refphinder. Once I get it and work out how to use it I will send you a recording and hopefully that free software I linked you in will be good enough to detect from where the reflections are coming from.

I also have some basic insturctions from Angelo on how to find spectral content of reflection from another software but I can't make anything from it. I will send it to you with the recording and maybe you can work it out.

Will keep you updated.

Sorry for the late reply. I can understand not wanting to spend more on more tools until after you are comfortable working with what you have. But congratulations on on the step forward on this project with getting a Zoom V3.

And thank you very much for keeping me updated and offering to share some files and software. I look forward to seeing what I can make out of that data.

 

[Trdat]

Sorry for the late reply. I can understand not wanting to spend more on more tools until after you are comfortable working with what you have. But congratulations on on the step forward on this project with getting a Zoom V3.

And thank you very much for keeping me updated and offering to share some files and software. I look forward to seeing what I can make out of that data.

Now, I apologize for late reply I didn't get a notification.

I still haven't yet tried to record with the Zoom but it is my goal to manage an attempt in the coming weeks. I can't imagine it being difficult, prepare a sweep on REW and then record it on the Zoom. I will record in A format and convert it to B format on the PC using the software supplied, I think I can manage that. Then I will send it through with the intructions posted, which might be useful for others as well on this forum.

I did find the Zoom H3 on Ali Express for $160 so if the above ends up being good you might have justification to purcahse it. But the most important for me is to understand spectral content so we'll work towards that as well according to the instructions supplied by Angelo.

 

[No. 5]

Now, I apologize for late reply I didn't get a notification.

No worries, my issue is usually that I receive a notification when I'm at work and I forget about it by the time I get home.

I still haven't yet tried to record with the Zoom but it is my goal to manage an attempt in the coming weeks. I can't imagine it being difficult, prepare a sweep on REW and then record it on the Zoom. I will record in A format and convert it to B format on the PC using the software supplied, I think I can manage that. Then I will send it through with the intructions posted, which might be useful for others as well on this forum.

Thanks! I'll be looking forward to seeing the data and instructions.

I did find the Zoom H3 on Ali Express for $160 so if the above ends up being good you might have justification to purcahse it.

Good to know, thanks for the tip on Ali Express.

But the most important for me is to understand spectral content so we'll work towards that as well according to the instructions supplied by Angelo.

For me too. Spatial perception is an huge part of preference, so having a way to measure that is very useful.

 

[Trdat]

No worries, my issue is usually that I receive a notification when I'm at work and I forget about it by the time I get home.

Thanks! I'll be looking forward to seeing the data and instructions.

Good to know, thanks for the tip on Ali Express.

For me too. Spatial perception is an huge part of preference, so having a way to measure that is very useful.

Hey,

I have attached a Wave File that has been recorded in A format and converted to B Format. The instructions were the following

Of course you need to record in Ambix format (ACN-SN3D).
Or, even better, record your impulse response in A-format and later convert to B-format Ambix on a PC, using the free software from Zoom (Ambisonics Player) and enabling the Ambisonics filter.
Unfortunately the processor inside the Zoom H3-VR is not powerful enough for applying the Ambisonics filter. This results in a subpar Ambix recording if the A to B conversion is done directly inside the recorder.
But this should not affect the spatial analysis of reflections.

I have done the above, the wave file is a B Format in ambix.

Next is the instructions on understanding info on reflections but not really instructions but what program can be used.

For visualizing the direction of reflections I usually employ:
1) the O3A Flare free VST plugin
2) My own IRspatial-Ambix visual mapping software, which you can download here:
http://www.angelofarina.it/Public/B-format/Software/
3) Some Matlab scripts developed by the Aalto University and available on Github.

But the next set of instructions are what gets me. So hopefully it helps you unless you have another way to get information on spectral content.

Regarding spectral analysis of a discrete reflection: after finding the direction of arrival using Flare or IRspatial, I synthesize a virtual cardioid pointing in that direction using the Rode Soundfield plugin.
The result is a mono IR where the reflection being investigated is strongly enhanced.
At that point I select a short segment of the IR containing the reflection and I trim it (silencing everything before and after).
And now you can display its spectrum, using Audacity's spectrum analysis tool.

Anyway, keen to see how you go. Thanks again for trying to work this out.

 

[aivs]

the wave file is a B Format in ambix

I'm trying to use your sweep data to look at how well the reflection angle is estimated as a function of frequency by the Zoom H3-VR. I expected a 4-channel (WXYZ) wav file, but there are only two. Did you only keep the Z-channel? Please explain. Thx

 

[Trdat]

I'm trying to use your sweep data to look at how well the reflection angle is estimated as a function of frequency by the Zoom H3-VR. I expected a 4-channel (WXYZ) wav file, but there are only two. Did you only keep the Z-channel? Please explain. Thx

Hey, I followed everything as per instructions but I will have another look and get back to you.

 

[Trdat]

So I had to rejog my memory, I am new to this.

I recorded on the Zoom in an A -format and then cut the sweep and converted it to B-format Ambix on the PC with the zoom software. From my understanding there is no other channel, just a conversion to B-format and that should do it. But then again, I am an amatuer, so if you have your own set of instructions I am happy to dig a little deeper to get to the bottom of it. I don't think there is a wave file, B format is a 4 channel from my understanding.