Loudspeakers & Microphones

• What do loudspeakers and microphones convert between?

  Sound waves and electrical signals
• How do loudspeakers generate sound waves?

  By converting electrical signals into vibrations
• What effect do loudspeakers use to convert electrical signals into vibrations?

  The motor effect
• What type of electrical signals do microphones and loudspeakers use?

  Alternating currents
• What is a key component of a loudspeaker's structure?

  A coil of wire wrapped around a magnet
• How does a loudspeaker work?

  1. Alternating current flows through the wire.
  2. Creates a magnetic field in the coil.
  3. Magnetic field interacts with the permanent magnet.
  4. Exerts force on the coil (motor effect).
  5. Causes the cone to change shape.
  6. Rapid vibrations create sound waves.
• What happens to the coil of wire in a loudspeaker when the current alternates?

  It moves back and forth along the magnet
• What do the vibrations of the cone in a loudspeaker cause in the air?

  Pressure variations that create sound waves
• What is the primary function of a microphone?

  To detect sound and convert it into electrical signals
• How does a microphone work?

  1. Sound waves hit the diaphragm.
  2. Diaphragm and coil move.
  3. Wire generates current in magnetic field.
  4. Frequency and amplitude of sound determine current characteristics.
• What part of the microphone moves to detect sound?

  The diaphragm
• What effect do microphones use to convert sound waves into electrical signals?

  The generator effect
• What determines the frequency and amplitude of the current generated by a microphone?

  The frequency and amplitude of sound waves
• What can the part called 'cone' in loudspeakers also be referred to as?

  The diaphragm
• What is the role of the permanent magnet in both loudspeakers and microphones?

  To create a magnetic field