Therefore, I have always tried new headphones between 10 and 100 euros to the unit in recent months. Again and again the same weaknesses: efficiency of headphones for iPod too weak, too little bass, exaggerated heights, no dynamics, etc. No one wanted to really harmonize with the iPod.
As a last attempt I have now tried the relatively inexpensive AKG K 24 P for once. Now the world is in order: high loudness, enough bass, high dynamics and all styles of music, clean drawing of all frequencies - just the music. It affects the sonic weaknesses of the iPod so contrary perfectly.
But be careful: bad encoded music reveals on these headphones weaknesses :-)