Poor mp4 audio quality with VS10

[hsinhow]

I got many complaints about the audio in my recent concert videos. An example can be seen/heard here especially with an earphone:

https://youtu.be/mHwv0Gr2cbA

Start from the beginning, you can hear that the audio seems to have high-pitch noises and the noise floor is high. This video is rendered using VS10's MPEG-4 4K 30p profile where the audio coder is AAC 192kb/s.

The audio was recorded using a Zoom H5 recorder in 48khz in 24-bit format and then it was synced with the video in VS10. The raw audio sounds fine and normal. As VS10 does not allow changing MPEG-4 audio encoder in custom mode (why??), I have used the combination of XAVC-S + LPCM to render the same sources and found the audio problem is gone. Therefore, the issue seems come from the AAC encoder itself.

I am not sure if the audio low bit rate (192kb/s) contributes to this issue. Given that I did not heard or notice poor audio quality from other videos in YouTube, I think 192kb/s should be sufficient.

Any thought?

hsinhow

[Terfyn]

Listened carefully through decent (Panasonic) headphones and the audio sounded fine to me bearing in mind that it would have been modified by YouTube. Also listened to the second clip (Magnificent Seven) and that sounded fine as well.

[asik1]

Well, one thing for sure, the audio is too strong by 3-5db

I downloaded the WQHD from YT and here you see that the audio is only 32b

So combining all that can not do justice to the piece.

*** I never used the zoom, but if that is what can be seen in the wide shot, than I think it's too low.

[TonyP]

Dynamic range of the recording can causes this. Trying to set levels when "low" and then when "high" usually requires a compressor to limit how "loud" the recorded music will be. I'm so happy to have a compressor/limiter in the audio chain at church. Listening to the YT recording on my desktop speakers (M-Audio BX5 Carbon and SuperDac II), it sounded fine to me also.

[hsinhow]

Thanks for everyone's feedback.

Controlling dynamic range is the reason for using the Zoom H5 recorder. (Camcorder/camera's audio part is highly distorted due to compression.) I have checked the raw .wav file and I think, even though there are a few positive dB spots, the recording itself is quite balanced, i.e. capture low volume/solo moments with high resolution and occasionally high volume part with minor compression.

The issue of this mp4 is the low volume part where AAC audio is very noisy comparing to the original recording. Yesterday I used CyberLink's PowerDirector to produce a mp4 file (from a XAVCS + LPCM audio source video file) and the resulting mp4 DOES NOT have the audio issue.

I still believe there is something wrong in VS's AAC encoder.

[asik1]

So why don't you test output as WMV?

[floyd_steinberg]

I know I'm late, but did you find a solution to this problem? I'm producing music videos on my YouTube channel and rendering the videos to MP4 produces horrible, glitchy audio. WMV is fine, but takes ages to render, and WMV can't do 4k. I tried the highest audio data rates possible, but things like hi-hats and snares (basically anything in the upper frequency range) sound like recorded through a water basin. Youtube isn't the culprit. Here's a wmv encoded video: https://youtu.be/f0RSzDeDeq0?t=110 (listen to the acoustic guitar and the string sounds) and here's mp4: https://youtu.be/9k4oSq7J1QU?t=30 (the flute sounds like someone's rinsing it with water while playing)

[asik1]

correct, there is something "attached" to the flute.
Well, I myself do not ever output mp4's out of VS but only wmv's as I consider the video much better also.
There is a "cheat" for 4k on wmv but I wasn't able to get it to work correctly in VS nor in WMM (I think only PD can do it), maybe another dll is needed.