Please note CHANGING the internal resistors does NOT inhibit you in the least from other cartridges in future; it is totally the way to go (assuming the simple change works for this circuit). If you go to 470, or 1000 Ohms, you can ALWAYS use an external metal short RCA Y adapter ($12) with two female/one male RCA and insert RCA plugs with resistors soldered inside. Parallel resistors will bring it down to what ever you need in future. (product of values divided by sum of values). We have seen this ONE load value in this model before, and it is very short sighted in my NSHO. The proper way is to have 1000 -2000 internal and at LEAST some open RCA females jacks on the rear apron, allowing you to put loading plugs in at will. If someone who knows circuitry can verify this circuit allows the 100 ohm resistors to be changed, let him know.....OR send ME the schematic. That is the lowest cost way to make this unit flexible like almost all models of MC preamp designs. Our high gain MCP-2 phono preamp ($1199) has a variable control to go from 10 Ohms to 5K Ohms. Another option.
Peter Ledermann/Soundsmith