At the sound, I noticed first that nothing strikes me. Unlike dozens of other headphones to more than 200 euros, which I tested in various electronics stores, which had very quickly sounded unpleasantly tinny through the middle, missing treble or bass booming. At the Porta Pro I had to get used not only simply latches course. Some people found the bass too. In the test with a sinusoidal signals I could find in any frequency band gain of volume, which is of course subjective and not measured. However, I have noticed that only give most speakers and headphones at low frequencies below 50Hz very little sound pressure, which is usually compensated for by an increase in the higher bass between 50 and 200 Hz. That's not the case with the Porta Pro. Also, the frequency response in the middle seems to me very straight, without a pronounced resonances. This problem is alleviated by lowering the centers in poor speakers normally. The Porta Pro sound without equalizer settings best and that regardless of the musical genre.
So far I have not found anything better, and enjoy the sound of every day.