Hi there, looking for some help looking for a closed full size headphone with the quality of detail, bass and excitement of the AKG K450. I did quite fancy the K550 but recent reviews have them as bass light. I've tried AKG 240s, lesser AKGs, ATH-M50, Senn HD600s and nothing seems to satisfy me with the same level of bass. I'm amping via a Vivid Technologies V1. Any help is most appreciated. Thanks.