phono stage volume

a phono step up transformer might do the trick. These are typically used when driving a MM phono stage with a lower-output MC cartridge. Or a phono pre preamp will also accomplish the desired level shift, & possibly allow you to experiment with various loading & gain settings.

Grado cartridges are not moving coil nor moving magnet; they're a hybrid design known as moving iron, basically a variable reluctance generator design. Some of their models are available with different-level output options, low, medium, high. Don't know what your X+ is set up for; give them a call to find out. You might be able to get a different model that's more suitable to fit your existing equipment.