System and method for broadband acoustic source

A method for making acoustic measurements in a wellbore environment, the method comprising:

• disposing an acoustic receiver into a wellbore;
• disposing an acoustic transmitter system into the wellbore, the acoustic transmitter system comprising:
• a carrier;
• a sound emitting member secured to the carrier, the sound emitting member comprising:
• a first mass coupled to the carrier by a first spring;
• and
• a second mass coupled to the first mass by a second spring, wherein an inner surface of the sound emitting member is sealed from a wellbore fluid by one or more seals;
• and
• an actuator configured to transmit energy to the sound emitting member;
• emitting an acoustic wave from the sound emitting member into the wellbore in response to the energy transmitted from the actuator;
• and
• receiving a received acoustic wave, at the receiver, in response to the emitted acoustic wave.