doucanoe asked for pictures, so I thought a thread might be in order. This is new to me, but not new. It's a passive preamplifier, a transformer volume control built around a pair of Stevens and Billington TX-102 transformers. Single input, single output with a mute switch. The previous owner bought it new, purchased from K&K Audio. They built it, and they certainly did a nice job! That's a Seiden switch. High end Vampire RCAs. Check out the nice knob, too! How does it sound? Pretty phenomenal, I think.