Consider a used Pass X250 amp. They go for about $3K. I have one and it sounds great with my Magnepan 1.6's. People who come over to my house are astounded at the powerful, tight bass that it produces through my Maggies. I use to have a Parasound A21 and it was blown away by the Pass. I have also heard the 400R and 600R amps with 1.7's and 3.7's. They sound great, very dynamic and detailed with great bass. The upper frequencies can sound bright with my Maggies unless you pair them with the proper preamp and source. The R amps keep their dynamics at low volumes, more so than other amps that I have heard including my Pass.