Hi Bill
You try to reduce the magnetic interference as best you can with internal phono stages and with MM stages it easier than with high gain MC stages. External phono stages eliminate the issue all together of course but add cost and connector requirements.
Its a tough call - I have not measured the the difference between our internal and our external phono stage but I have the MM stage in the BP-17 Cubed at home with the Bryston turntable and an Ortofon MM cartridge and have no issues at all. I also have the BP26 with the Bryston turntable and the external Bryston MM/MC Phono Stage with the PS3 power supply and a BENZ moving coil and it also performs very well.
Hows that for a political answer !!!
james
Hello James , Do you remember what model Ortofon MM Cartridge you used also what model of the Benz Micro for MC?