I'll keep this very short.  They are very smooth sounding.  Treble toned down so not so good for rock but have a magic about them that makes them better than mark 2.  I use them with a '89/'90 Marantz PM50 integrated.  Very powerful amp with a great headphone out.  Don't need to go past ten o;clock even with these 600 ohm babies. Anyway, great vintage headphones that are well made and worth a go at the right price.