popping sound in AAC files created from nero

[jk888]

Hi, I seem to be getting a popping sound on AAC files created from nero. It happens when I transcode a AC3 file into 5.1 ch AAC low bitrate with HE. I tried using all builds of nero from 6.0.0.11 to the latest 6.0.0.28, but I still get the popping sounds. The AC3 file is created from XMPEG ripped from DVDs (tried multiple DVDs same prob). The AC3 file plays fine with no problems.

Here's some results of my testing:

AC3 -> AAC HE Internet profile = popping sound
AC3 -> AAC HE Radio profile = popping sound
AC3 -> AAC HE Tape profile = popping sound
AC3 -> AAC LC Radio or Tape profile = popping sound
Ac3 -> AAC LC Internet profile = sounds normal
AC3 -> AAC HE Streaming or Normal profile = sounds normal
AC3 -> AAC LC Streaming profile = sounds normal

I used the nero AC3 pluggin (set to 5.1 ch) to produce these results, but I also tried using BeSweet to create an AIFF file then convert to AAC using nero but the results are the same as above. Can anyone shed some light into this? It seems to happen only in low bitrate or HE situations. At first I thought it was the AC3 pluggin but now I am beginning to think it's the nero AAC.

[The Edge]

Did you try using 44000khz instead?
I have no got HE-AAC to work on system at home either.

Edge

[bobsc]

Try OagMachine and downsample to 44100Hz.

[Tuning]

Do you enabled PNS, or any other options in config window ?. That can cause this kind of problem.

Btw, what player are you using?

[K-Dash]

Oh yes the favorite popping sound, this is very anoying sometimes but I think its some sort of a bug in the encoder. Since I've gotten that popping sound quite alot of times and whenever I reencode it again maybe once or twice or more times untill the popping sound is gone. I'm not so sure what causes this but what you can try is what I did and to reencode it all over again at same settings u used from before, but when you use bsn to encode u'll never find that popping sound from what I've experienced.

EDIT: I forgot to tell you guys that this has only happened when I'm encoding 5.1 AAC and not Stereo.

[The Edge]

Disable PNS for 5.1 and use LC profile. All will be fine. I use the 3ivX audio decoder and/or the CoreAAC decoder.

Edge

[K-Dash]

The Edge solution is safest imo if u dont wanna play around with it, but then again u get a file which is larger than expected and the quality arent much different either.

[The Edge]

I've yet to test the Nero Recode solution.
It can do 5.1 aac apparently

Edge

[mfluder]

The solution is not to use 'Settings' dialog from 'Encode files' window. You can view settings with it and then click Cancel but you must not click OK. Even if you don't change anything and click OK you will have this problem. I know this sounds strange but it's true. This problem only appears with 5.1 and only when HE AAC is used, LC AAC doesn't have this problem. If you have to change encoder settings you must do that from Nero's preferences dialog: File -> Preferences -> General tab -> Plug-in lookup -> Encoders tab and there you configure the encoder.

I already posted about this in that long thread about AC3 plugin. Anyway, I no longer use Nero for encoding. Why should I when DSPguru gave us possibility to use it with BeSweet :D I suggest you do that too. You can find lots of info about BeSweet and BSN on this forum. Search button is your friend ;)

mfluder

[jk888]

Wow it's amazing the amount of brain storming I generated from this thread. Thx mfluder, that is an interesting solution with the "settings" button, I have yet to try it but I definately will later on the weekend.

Also I'd give a great thx to all of you, Tuning, K-Dash, The Edge, and bobsc. As most of you suggested tried to encode with BeSweet again but this time the only difference is I used 44100Hz, and I was able to create a Radio-HE AAC file with no popping sounds. Though I was disappointed in having to downsample, I was also knew the history of 48000Hz issues with nero in various other posts already in this forum. Oh well maybe it'll get fixed in the future.

I look forward to Nero's Recode2, I really hope it has a built in AC3 encoder/decoder that menno has tested with Nero Digital. This is kinda like asking Santa what I'd want for Xmas hehehe :p

[KpeX]

Hi jk888,

Welcome to Doom9's forums! I'd like to congratulate you on a good first post, and a great job of letting us know that the solutions given to you worked, and how you were able to solve the problem. Confirming how you solved your problem is critical so that users who have the same problem in the future can research possible solutions. Every newbie should take note of such an example. Cheers,

[jk888]

Hey Cool! Now when do I become a senior member hehehe :D .

Anyways I did some more testing, this time I tried what mfluder suggested and used nero (AC3 plugin + 5.1 channel wav.dll) without touching the "settings" button and it worked. I created a 5.1 channel 48000Hz Radio-HE profile AAC file without popping sounds. But for some reason the sound wasn't centered, it was more to the right, the 5.1 channel mapping is incorrect I think. Strange because I set the AC3 plugin to 5.1, I pushed the 5.1 button in the plugin settings. Anyone know about this?

[bobsc]

What version of Nero are you now using?

[jk888]

The current newest one, 6.0.0.28.

[Tuning]

Hi jk888,

As everybody suggested, use BeSweet/Bsn and Oagmachine(GUI for Besweet/BSN ) for your AAC files.
The guide can be found here (http://www.doom9.org/oagmachine.htm). As you are using 60028(new) version of AAC codec, you need to use 5.1ch(new) setting in Oagmachine. If you are going to use LC-AAC (just making future proof ;)) then you have to do resampling at 44.1Khz.

I think (not sure about that, as I never use Nero ac3plugin) this nero ac3 plugin is not updated to channel ordering change from version 60015. So that might be your problem. Another chance is the player you are using. Currently 5.1AAC is correcly decoded in foobar2k, CoreAAC and 3ivX audio decoder. So if you are using winamp, then there is a probability of wrong channel mapping.

Happy Encoding!