I own the HPM’s, bought a pair new in about 1977, drove them with a Pioneer SX-750. They’re easy to drive and have a classic sound. That being said, it’s hard to say which speaker will be better, after nearly 50 years, either will probably need some restorative work. Same with your Marantz .I still have the Pioneer, as well. This stuff is like owning a classic car. Endless fiddling, and almost anything new will perform better. And yet, sometimes you can’t help yourself, lol. Good luck. For room treatments, it's hard to go wrong with a couple of macrame' hangings, and a poster of Farrah.
