First of all i been reading the forum for sometime and what grate forum, ok lets start it since i found out about the aac itunes encode i was satisfited whit 128 aac and then start to listen closer and notice some diferences on cd and aac files so i move up to 256 vbr aac and was ok for a few days until i test it on a pro system (jbl vertec) and yamaha console ls7 and found a big diference the highs sounded distorted and middle frequencys, so i move to ALAC just the favorites songs and gained a few gigs on the ipod so started to look around and read comments so i move back to 320 aac because the sapce and found, that is wasted of space since the ipod dosent have a good output and dosent make any difference so its not good for a portable player, and then found this forums and start to look around , and start using the foobar2k and made some test on diferents format songs mp3, aac at diferent bit rates using visualation spectrum and found out similar range on 320 acc itunes and 225 mp4 nero codec so i am sticking around to the nero encoder for a while until that little wondering appears again especially reading this forums, and sorry for my english its not really good

Did you actually conduct blind ABX tests using your headphones or do you just feel that you hear a difference between 128kbps AAC (always enable VBR encoding) and 256kbps AAC? Some of the latest listening tests show that 128kbps is very capable and it should be fine for portable listening as most portable environments cover up frequencies that allow you to take advantage of higher bitrate music.

If you have conducted a blind ABX test then alright. Are you looking for some advice or something about using Nero AAC? You should use the -q settings as they produce VBR files that use the encoder more efficiently than CBR or ABR settings. The default -q value for Nero is -q0.5 which produces files around 170kbps VBR (though the newer version of Nero AAC seems to produce files around 190kbps VBR at that setting). If you decide to go back with the iTunes AAC encoder then make sure you always enable VBR encoding. VBR encoding (whether it is Lame mp3, iTunes AAC, or Nero AAC) allows a encoder to be used more efficiently. Bits can be assigned where they are needed and bits can be lowered when needed.

Don't worry about what your music looks like; pay attention to what it sounds like. What it looks like is unimportant, because it's for listening to.

How much attention you want to pay to the sound quality is another matter. Apart from anything else there's a difference between paying attention to the music and paying attention to the quality of its reproduction. After all, people still buy certain old and poorly engineered recordings, because of the musicality of the performers. I think one could direct one's attention so much towards the sound quality as almost to miss the music. But obviously most people would not want sound faults that are so evident as to call attention.

If it really matters to you, you'd be best to do blind testing, as has been suggested. Here's the reference in the knowledge base here to that:

http://wiki.hydrogenaudio.org/index.php?title=ABX

At the end of a day, it's a trade-off between what quality you're prepared to accept and how much room you have on your hard disk (or portable player). But rigorous testing often pleasantly surprises people in that they find they can't pick one sample from another when they'd assumed they might be able to, enabling them to use lower bitrates and thus have more music.

Thats very true, because i am making the idea lower bit rate less sound quality i will try the abx test and see what the results are

dumb question but still learning, how can i change the -q setting on the nero encoder

foobar2000 has a built-in profile for VBR encoding of Nero. Simple select the mode of Target Quality. You can then slide the Quality meter left and right and a small box should display the overall average bitrate along with the -q value.