Moving Coil Phono Step Up w/ Haufe ST-5863 1:15/1:30 Transformers MC SUT

Description

Here's a step up transformer box to bring moving coil phono cartridge output level up to moving magnet levels so they can be used with standard moving magnet phono preamps. This box uses a pair of German Haufe ST-5863 transformers. These transformers give a 1:15 step up ratio on the low gain setting and 1:30 on high. Assuming your phono preamp has standard 47k ohm input resistance, these setting will load your cartridge with about 200 and 50 ohms respectively.
These are 1980's vintage transformers, so a little newer than the old Siemens/Klangfilm transformers that were also made by Haufe, but they do have a very nice, refined sound with a very smooth top end, very smooth and natural sound. These transformers are terminated to pins, so they sit on a little PCB wafer rather than the bushing mount of the older Haufes.
The ground switch selects how the aluminum chassis is grounded and gives you a few options for wiring. In the middle position the two audio grounds and the box are all kept separate from each other. In this position you need to run a separate wire from the SUT's ground post to your phono preamp ground post to be sure that the box is grounded and provides shielding. For convenience you can also attach the box to the left audio ground (in the "L" position) or you can tie all three grounds together (in the "L+R" position). Usually you don't have to think too much about grounding, just wire the box up how you like, and then put the switch in whichever position gives the lowest noise.
If you have any questions, please feel free to ask. I'm always happy to help if I can. Thanks!