The very first Beyerdynamic DT 990 was released in 1988. It was considerably more hushed back then. However, the previous DT 990 has sparklier highs that are seamlessly increased.
The Beyerdynamic DT 990 is a very well-made conventional headphone with no surprises. When the earpieces are put away, they tend to move up into the harp on their own. And, after decades of technological improvement, the new model is crisper and more durable.