Very very good can , well appreciated here or there by experienced audiophiles. it's close to neutral but keep a "Ultrasone" touch : impressive bass quality (deep , textured , clear and impactful) , clear extended trebles but never harsh, dynamic and energetic overall sound. The Sig pro add very good mids too in order to be maybe the more balanced/neutral Ultrasone. Soundstage is good with very good depth but less width than the best open cans. It's not a deal breaker although you listen only to Symphonies IMO. At last, sound presentation is quite forward and immersive.
Extremely good headphone in my opinion; very detailed and accurate . Maybe a bit cold but this point is inherent to its temperament. A tube or hybrid amp can bring all necessery "humanity' to compliment perfectly the Sig pro. You must notice the SP don't need any amp to perform very well although a suitable amp brings the SP to its best.
Definitely one of the best choices in closed can . You can also consider the Signature DJ which is globally the same with a more V-shaped signature. Maybe a better choice to get more bass with the same overall quality. it's a matter of preference or Musical tastes.
Isolation is perfect. Comfort very good ( maybe clamping is a bit strong) . Sig pro is build as a tank and has an inconspicuous appearance. If you prefer Luxurious aspect , it's not the best choice :)
After all, it's a refined , accurate , detailed headphone. It don't "wow" you at the first listening like more "fun" cans. but after few hours when ears and brain are washed from bad habits , the truth finally come .
Edited by Sorrodje - 1/15/13 at 12:57am