Here some photos of a passive transformer volume control which I just finished.
Independent volume control switches for left and right channel. The two jacks on the left side are for headphones (both wired in parallel).
The unit uses Intactaudio AVCs (auto former volume control). Here a shot of the inside before it got mounted into the wooden enclosure:
Just single sets of RCAs for inputs and outputs.
The unit is similar to the passive line stage which I showed last year, except that it has no input selection switch but just a single stereo input.
Passive AVC units like this are meant for use with low impedance sources which are known to be able to cope well with the inductive load. Otherwise active line stages are my preferred solution.