Ponder on, dude. I'm chiming in to share a wee bit of beauty and frustration regards an old MC step up device. I own a Marcof PPA1. It may even be the original battery powered step up device and maybe that would qualify as vintage. Rare, anyway, I expect. A week ago, one evening, I decide to dust it off. Put in new batteries and it lit up. S***, I'm gettin excited! So, after a while, I put it in. Couldn't hear a thing and I almost gave up but decided to crank the volume and there it was! What I had forgotten was that when I bought it I was steppin up an MC using a full preamp. Now, I'm using a line stage. So, I could only get enough volume to hear a sweetness and clarity that made me wish. Even with a high output design. Damn! Do I ever wish this tale had a happy ending.