If the system is modulated by the speach
coil, a simpel measure of how well the system resists this modulation,
is the ratio of resistance to inductance of the field coil, lets call it
Fc. If the insulation thickness of the field coil wire is
negligable, this ratio is unchanged and therefor the dynamic behavior
will be the same as well.
Real insulations have a thickness and
this inperfection will tend to upset the ballance, so that higher
voltage coils by unchaged statical flux will tend to be softer (higher
Fc) or more easy to modulate and therefore the unit will have higher
distortion due to the magnetic nonlinearities of the pole pieces.the high voltage coil will at the same flux have higher
dissipation, this could mean that it will run at a higher temperature
and thereby softening the mooving parts more. If this is the case and
is benneficial, the resistor mentionned in the post above could be
mounted at the back plate of the electromagnet or the magnet could be
insulated to run at a higher temperature! |