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The usual procedure is to select input jacks on phono pre-amps based on cartridge
type, Moving Magnet or Moving Coil. As previously indicated the XP-27 is not
typical and is designed to simplify your life. With the XP-27 cartridge types will be
accommodated by gain and loading selections from the XP-27 front panel.
In general MM (moving magnet) cartridges will require a gain setting of 53 dB, MC
(moving coil) a setting of 66dB or 76dB. Moving Iron cartridges, usually 66dB. However
there are no fi xed rules, the requisite setting is that setting which works best in your
situation. Some listeners will select gain based on a sonic preference others simply
will choose a setting that brings their phono system output on parity with their other
source components. Either choice is equally valid.
Moving magnet and moving iron cartridges typically work very well with a series
loading of 47k-ohms and 100 pf of parallel capacitance. Like gain, these settings
too are selectable from the front panel of the XP25. Presuming 47k-ohm in the case
of moving magnet, greatest benefi t comes from exploring the pallet of available
capacitive loading choices. Infrequently moving magnet cartridges will perform
best at other than 47k-ohm but that would be an exception. Moving Iron cartridges
typically load @ either 47K or 1K ohms.
Moving Coil cartridges frequently do best with lower impedance loads and see
little advantage from additional capacitance. From the front panel your choices of
cartridge loading will be as follows:
Resistive loading choices; 30 ohm, 50 ohm, 100 ohm, 160 ohm, 250 ohm, 320 ohm, 500
ohm, 1k-ohm, 47k-ohm
Reactive loading choices; 100 pf, 200 pf, 320 pf, 430 pf, 530 pf and 750 pf.
If you have other than a moving coil cartridge, please take time to read the short
treatise on moving coil cartridges, the philosophy and exercise of how one might go
about adjusting for a particular cartridge is not exclusive to the moving coil.