Loudspeaker protection circuit responsive to temperature of loudspeaker driver mechanism

A loudspeaker system, comprising:

• a loudspeaker driver mechanism adapted for connection to a signal supply mechanism for providing an electrical signal to the loudspeaker driver mechanism;
• and
• a thermal protection circuit connected in series with the loudspeaker driver mechanism, the thermal protection circuit comprising:
• a load device connected in series with the loudspeaker driver mechanism for reducing a power of the electrical signal before reaching the loudspeaker driver mechanism;
• and
• a first normally closed, thermally sensitive switch connected in parallel with the load device and thermally connected to the loudspeaker driver mechanism such that heat generated by the loudspeaker driver mechanism is at least conductively transferred to the first switch, the first switch being changeable between a closed state wherein the load device is at least substantially bypassed, to an open state wherein the electrical signal is at least substantially directed through the load device when a temperature of the first switch is above a predetermined temperature and the electrical signal is above a first predetermined signal level.

A method of protecting a loudspeaker system against thermal overload, the loudspeaker system having a loudspeaker driver mechanism adapted for connection to a signal supply mechanism for providing an electrical signal to the loudspeaker driver mechanism, the method comprising:

• connecting a load device in series with the loudspeaker driver mechanism;
• connecting a thermally sensitive switch across the load device, the thermally sensitive switch being changeable between a closed state wherein electrical current from the electrical signal is at least substantially directed through the thermally sensitive switch, and an open state wherein the electrical current is at least substantially directed through the load device;
• increasing the temperature of the thermally sensitive switch by conductively transferring heat from the loudspeaker driver mechanism to the thermally sensitive switch and by directing the electrical current through the thermally sensitive switch;
• and
• automatically changing the thermally sensitive switch from the closed state to the open state when the temperature of the thermally sensitive switch is above a predetermined temperature and the electrical current is above a predetermined current level.