Summary: Bought these because they were highly recommended by Which - big mistake - it is almost impossible to hear anything through them unless the volume on my MP3 player is turned up to its maximum. Impossible to use them outside! Which has said that new EU Regulations have forced headphone manufacturers to lower the volume to protect people's hearing. However, I tested several other makes of headphones in Currys recently and they were all fine i.e.
Summary: When buying an expensive pair of headphones you expect a certain level of build quality. The headphone plug is of such a poor plastic construction that screwing on the included plug adaptor causes the plastic body to rotate within the plug assembly and severs the cables inside the plug rendering it useless. Do not buy!!!!!
Summary: Unfortunately, the Beyerdynamic DT770 PRO 250 OHM are not a good choice for professional users. I had problems with low end distortion within two years of purchasing. I sent them for servicing via the warranty cover and received the headphones back with a fresh set of ear-pads, but with exactly the same technical issues. Last week, one of the drivers died, inexplicably, dead, nada, nothing. They are out of warranty now, so how much for repairs?