How can i tell if my Motorola E1 ROKR (itunes) supports any version of HE-AAC, as i understand it is backwards compatible and so would play anyhow just with lower quality. any way i can test and know for sure?

put an HE-AAC encoded file on your comp and on your Motorola and see if you can ABX the difference :\

if the sound of he-aac file is dull and without highs, then it decodes only the lc part

Encode an LC-AAC file at 22khz and ~64kbps, then encode an HE-AAC file at 64kbps. If they sound the same, the HE part isn't working.

Thanks for all your help.

For future reference:

The MOTOROLA ROKR E1 support LC only without PS.

Does it support SBR or not?

I used Winamps CT encoder, no special features works but the plane LC encoder so i guess the answer is no.