McIntosh MA6300 vs. Mark Levinson 383 Integrated

The McIntosh MA6300 I heard had difficulties driving an ATC SCM 11 V1. Tough to comment on SQ when the amp was pushed. Would what a very efficient speaker for the MAC. The Levinson 383 was demoed about 20 years ago(lol) it had an open spacious airy(whitish) type SQ not a muscular type of sound of the Krell(300 IL). IMO the Jeff Rowland Concentra 1 or 2 was clearly the best sounding integrated amp from that time period. 

Thanks dayglow. My speakers are Revel F30. I’ve read the Concentra integrateds are very good.