It is hard not to notice that at any given preset, the latest Nero AAC encoder is producing higher bitrates. Without extensive testing it seems that streaming, transparent and extreme presets nearly match the bitrates of the Lame medium, standard and extreme presets, respectively.

Needless to say, the approximate bitrates given in the Nero program when selecting these bitrates are outdated. Hardly a serious bug.

Nero AAC, and AAC in general, is going through a period of development that appears to be at a rapid rate compared to the somehwat glacial (or even geological) pace of development for other codecs, so I expect this is part of the process.

However, I wonder if this was a choice by the developers to produce similar bitrates to Lame so as to allow for "apples to apples" comparisons that were not possible at the previous bitrates, a feeling that the "transparent" setting was not transparent enough, or just the result of tuning without new labels.

Any light that the developers would like to shine on this would be appreciated.

Names of the presets and average rates were measured long time ago.

In last 6 months, there have been lots of replacements of some key algorithms in Nero AAC (namely tonality calculation in psychoacoustic module, TNS module, addition of some new algorithms in psychoacoustic model, new ATH, etc...) that certainly increased bit rate under same coding conditions.

Also, we introduced new releasing model with much more professional listening tests inhouse - which will probably generate new values for the VBR presets soon.

Last change was ATH replacement, and it is probably responsible for the bit rate jump in 2.6.1.9

I expect, in the next version, to have VBR presets with decreased bit rate but with keeping the quality - but the process is not very easy - it is very time consuming.

I forgot - for the upcoming version of Nero AAC we do plan to perform more tweaking of VBR presets (including medium and high bit rate), to tweak HE-AAC core for very low bit rates - and, some new features that are still secret

Thanks for the peek at the future, Ivan.

Secret new features? Oh boy! Every month when a new version of Nero comes out it's just like Xmas (I hate xmas, so actually its not like xmas at all, but you get the idea) and improved AAC is the present! I can't wait for the new version. Thanks for all the hard work Ivan and Menno!

I am not sure if they (new features) will be finished for the >next< version (March) but they will probably come very soon

Always a pleasure to hear of new Nero features Ivan. Keep up the good work. I look forward to the new bitrate optimizations. Too bad, they weren't done and released before rjamorim's upcoming AAC test.

BTW, any plans for supporting a user selectable option to toggle saving with a .m4a file extension instead of forcing the .mp4 extension on all file save operations in Nero? Thanks.

I think tweaks with regards to the presets that might be used in Roberto's test will be finished before testing starts. Low and high bit rate tweaks will be finished afterwards.



Sounds like a good idea - I think it is doable, but I can't promise it until we figure out where exactly to put in into GUI.

Ivan, thanks for your comments above. Maybe you could find a place for a check box for the .m4a file extension option on the bottom of the encoder GUI options screen that pops up when they click on "Settings", i.e. the page that lets them select Preset, Encoder Quality,Bitrate, Enable PNS, Export ISO AAC track, etc.

It would be a much appreciated feature (and save lots of extension renaming for iPod/iTunes users).

Nice to hear that you may have new tweaked version for rjamorim's 128k test also.

Ok, I'll see what I can do.

...scratching head, wondering if I should stop my mass-encoding with 2.6.1.9 and wait for the next version...

edit : version number

I've stopped until next version. The whole point of AAC for me was to gain smaller file size for the iPod. I'm very happy with the sound quality of MP3 LAME APS - just not the file size. I'm sure Ivan will be able to keep the quality improvements and get the file sizes back down to what they were.....it will just take time.

Fist off, thanks to Ivan Dimkovic and his team for advancing the state of AAC so quickly!!! It seems like every month improvements are being made. Also thanks for actually reading these boards and taking suggestions!

I have a question for the Nero AAC development team. Do you feel that these monthly improvements to Nero's AAC codec are significant changes or minor tweaks? I only ask because I think there are several HA people that are or are about to be creating AAC collections. I, for one, have stopped mine and am going to delete the 800 files I have created as I want to take advantage of your new codec (once you have optimized the bit rate and reduce transparent file sizes). Do you have any idea on where you are at in AAC development?

I will begin my AAC collection encoding when 'signifacnt' changes are done (like the last change) and your team is in the 'making minor tweaks' stage.

Until that time, I'll just continue to use good old MP3 LAME 3.90.3 APS - which still work on every iPod out there - but I'm looking forward to conversion to AAC. The sound of your AAC codec at the transparent setting (to my ears) is awesome! Just waiting on file size reduction.

Thanks if you see this message and have a chance to respond!

There won't be any significant changes in LC part of the AAC (128 kb/s and up) - except for polishing some presets, fixing some problem samples and decreasing bit rate (without loss in quality of course)

However, at low bit rates - there will be a lot of improvements.



I don't think that there would be any dramatic improvements in high bit rate area - except for fixing some problem samples. Maybe the bit rate will drop between 10-20 kb/s without quality loss.



It will probably happen in the April version of Nero AAC encoder - depending on a schedule.

Again, thanks to Ivan for being so responsive!!!

April is my target date then to begin my AAC collection.