Unwanted signal noise hiss is heard in the recording.

country_hick

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I am pretty sure there is to much static (hiss) here. I uploaded a raw file to vimeo here


Can anyone verify if this mobius maxi is defective or not?

I uploaded a raw file to vimeo. I tried reducing the audio from high to medium and still hear static on my end.
 
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Mine's a lot quieter. Are you powering it or is it running off the battery?
 
@country_hick - What you are hearing is not static but a hiss cause by the S/N (signal to noise ratio) which is a background noise common to all electronic audio devices which have this to one degree or another. SNR is defined as the ratio of signal power to the noise power, often expressed in decibels. For some reason your Maxi unit is apparently louder than others. If you have a stereo system in your home and you turn the volume up all the way with no music playing you will hear the same exact sound.

Try setting the camera to a lower Audio Recording Volume and see if the hiss level is reduced or goes away entirely. This will help confirm the problem.

Max-msetup.jpg
 
I put the sound recording at low. I had previously tried it at high and medium with the same results.
The noise is still there.

I find this very frustrating. This level of noise ruins a recording.

P.S. At 2mbps internet speed uploading these big files takes way to long.



Snap 2018-07-29 at 21.25.01.png
 
If what you are saying is true then it sounds like you received a defective camera since you are the only one reporting this so far, unless there is some other explanation. Try returning it for a refund or replacement.
Before doing so, see if a different memory card makes any difference.
 
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I received this reply about the noise.

Hi friend,

Thanks for your reply. My friend, we can open the link and download it this time. We have checked the sound of the video, it is white noise. It's because of the auto gain control. When the environment is rather quiet, the auto gain will increase a bit trying to capture some level of sound. The gain increases, the background noise white noise increases. When there is any human voice or regular sound, the gain will be back to normal again. There is really not much we can do. We can not turn the auto gain control off, or the sound quality will be not balanced and not pleasing to hear. It is same for our other camera, like #16 camera, mobius 1 camera and mobius 2 camera.

Sorry for the confusion.

Regards,
Mandy
 
That is not too bad considering the low sound level being recorded, most action cameras would fail to catch your voice in anything like that detail because they wouldn't let the auto gain control turn the volume up that much. If you don't like it then edit the sound and turn the volume down to quarter and you may find it perfectly acceptable. No action camera is brilliant on sound, for perfection you need a dedicated audio recorder.
 
I received this reply about the noise.

Hi friend,

Thanks for your reply. My friend, we can open the link and download it this time. We have checked the sound of the video, it is white noise. It's because of the auto gain control. When the environment is rather quiet, the auto gain will increase a bit trying to capture some level of sound. The gain increases, the background noise white noise increases. When there is any human voice or regular sound, the gain will be back to normal again. There is really not much we can do. We can not turn the auto gain control off, or the sound quality will be not balanced and not pleasing to hear. It is same for our other camera, like #16 camera, mobius 1 camera and mobius 2 camera.

Sorry for the confusion.

Regards,
Mandy


"White noise" is simply another way of saying the same thing as "signal to noise ratio" which results in the "background noise common to all electronic audio devices which have this to one degree or another" that I described in my first reply to this thread, otherwise known as the noise floor.

As a result of the message you received from Mandy at eletoponline365 I did a little testing with a Maxi as well as with a Mobius 1. I put both cameras into a sound deadened space (a clothes closet) and let them record for a while. The Maxi produced the same exact S/N hiss (white noise) that yours does. The Mobius 1 creates an absolutely dead quiet recording.

I had never noticed this before and I don't think anyone else would have either when using the Maxi in an automotive or FPV environment where ambient noises would drown out any low level hiss. Nevertheless, I think you've unearthed a previously hidden flaw in the Mobius Maxi. I'm of the opinion that the camera should not do this. The AGC (automatic gain control) seems set too high. When I recommended trying a lower audio volume setting I thought perhaps the AGC would be turned down as well but apparently that is not how it works. The AGC issue here is equivalent to what I decribed when I said, "If you have a stereo system in your home and you turn the volume up all the way with no music playing you will hear the same exact sound." As far as I know, the AGC level is something that Mobius can address in a firmware update, assuming that the chipset itself doesn't inherently have a S/N ratio that is so low that the noise floor can not be compensated for.

One of the things that has always impressed me about the Mobius 1 camera is the outstanding audio recordings it is capable of. In many situations carrying the Mobius as a pocket camera I have used it as a stand-alone audio recorder with excellent results. Using the camera to record wildlife in natural settings the perfectly quiet but sensitive recording is also impressive.

If the Mobius 1 can produce such clean, quiet recordings, then the Maxi should too. At the very least, it should be quieter that it is. Nobody should have to turn down the sound on a recording to get acceptable clear audio, especially on a camera that is being used to capture evidentiary documentation.

Mobius should add this issue to the list of things that need to be addressed in any future Maxi firmware updates!
 
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My experience is quite the opposite. Both my M1's are noisy as hell, whereas my Maxi has negligible noise.
 
My experience is quite the opposite. Both my M1's are noisy as hell, whereas my Maxi has negligible noise.

Interesting.

FWIW, I did this test with a brand new M1 that arrived in the mail yesterday. I purchased it to replace one of my older M1s that failed suddenly for no apparent reason. When I get some time later I'll try the test again with one or more of my older M1 cameras but TBH I'm not expecting any different results. I'll report back.
 
I am hoping that mobius (to version 3) is comparable to MS windows.
Every other version of MS windows works great. the remaining versions of windows never were well liked.
Mobius 1 is great. Mobius 2 flopped, Mobius 3 (maxi) is (hopefully) great.
 
Ok it's not negligible but way lower than some of my other cameras.

This is what I'm getting indoors. Off the battery or with a power bank, not much difference.


This is what I got in the car


About the same.
 
I would say the hiss is prevelent even when the maxi hears voices.
The hiss remains when voices are captured.

P.S. This was taken to capture footage of turkeys walking by as a test.

 
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Had an amazing flock of 24 wild turkeys wander through my front yard a few days ago, three big hens and 21 poults!

That hiss sounds pretty loud. My Maxi doesn't seem to do that.
 
How AGC works is based a lot on where it is put into the circuit. Any is better than none, but it can be done quite well, and better than this. Having said that, these are not meant to be high quality audio recorders and with the SOC approach there may be nothing Möbius can do about it. One workaround would be to use an equalizer during playback, and lower the treble response. That will improve the sound somewhat as most of the sounds you want to capture here are lower in frequency.

Phil
 
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