Different standard necks, different pickups, different preamp... and yet I think they sound similar (from what I saw from internet videos). The M series has a blend pot and a 3-band equalizer (boost/cut). The L series has a pickup switch, a series/parallel switch, a active/active with high boost/passive switch and treble/bass controls (cut only). So they have pretty different control schemes and they probably can achieve different tonalities, but I think the MFD tone underneath them is the same on both...
The pickups are different wounded. I believe the M series Pickups have less wounds, but I might be wrong.
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