Yes, that's a big help. It's an original Paramour, probably the second version with the C4S included.
The 10H choke (C7-X) is the plate choke, and the output transformer uses the 1.25 watt tap which translates to a 4K primary impedance. You have the original output transformer, which was replaced later with the "Speco" transformer when the original was discontinued. It took us a long time to find a transformer as good as the original. The Speco has since also been discontinued - that's when we converted to our own custom parts, for the Stereomour.
There was an upgrade setup - I can't locate the web page, but I think it still exists. As far as I remember, it accomplished the following changes:
1) The 10H choke remained in place but electrically it replaced the 270-ohm 5-watt resistor in the high voltage power supply.
2) A new plate choke, Magnequest BCP-15 (40H at 50mA), was mounted on 1" standoffs below the chassis plate, using the 10H choke mounting screws.
3) There was a custom output transformer, rated 4K to 4, 8, or 16 ohms, which replaced the original output transformer. The new one was a bit larger, and mounted at a slight angle.
The upgrade output transformer has been out of production for a long time now, unfortunately. I see two possibilities for upgrading, following the original plan fairly closely. This will make more sense once we locate the old instructions!
There are no kits or instructions for either, and as far as I know neither has been done so far. Here are the possibilities:
1) The current Paramour II upgrade iron from Magnequest, BH-5 outputs and BH-6 plate chokes.
http://www.magnequest.us/ The output transformer should fit I believe in holes that already exist, but it has exposed solder terminals rather than lead wires. These terminals must be insulated after wires are attached, for safety reasons. The choke is the same size and specification as the BCP-15 and can mount the same way. The output transformer is 3K ohms impedance, but that is enough to work well in this circuit as long as the larger plate choke is also used.
2) The current Stereomour uses a 20H plate choke (PC-3) and a 4K output transformer (OT-2) which are the same size as the original upgrade parts. The output transformer again has exposed terminals. These parts are not yet being sold, but there are plans to offer them as an upgrade to the older SEX 2.0 amp so they will probably be available.
I'm afraid that's the situation at the present time.
