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Speaker technology comparison

Speaker technology comparison

Speaker Technology for Balanced armature and moving coils use different technology principles for producing sound pressure and consequently they differ in construction.

Balanced Armature

  • The balanced armature speaker is the preferred technology in applications where efficiency (battery life) and size are critical parameters. This is for example the case in hearing instruments, in-ear earphones and various military and security headsets.
  • Balanced armature technology offers substantially more output per mm³. This is an advantage in miniaturized applications where you want to fit several speakers in a small area (e.g. to produce hi-fi earphones with tweeter, mid and bass tones).
  • Power consumption Very Low Balanced armature technology is fundamentally more efficient of transforming energy into sound.
  • Balanced armature earphone are not leak tolerant and should be sealed tightly in the ear otherwise the low frequency (bass) disappears.

Moving coil

  • Moving coil speakers (dynamic speakers) are the most commonly used technology. Moving coil speakers are used in for example cell phones, loudspeakers, headphone and basic earphone designs. This design requires more current and they are larger in size.
  • Moving coil speakers by design offer greater undistorted maximum output.
  • Moving coil speakers are cheaper to design and manuacture
  • Moving coil eaphones are leak tolerant between the ear and the speaker since it works as a general loud speaker.

Technology Balanced Armature (BA) Speaker

Speakers Working Principle

How do BA speakers work?

  • The speakers are based on the balanced armature principle. The armature (a metal strip) is placed between two magnets and a coil is placed around the armature. The armature tip is positioned exactly in the center between two magnets (balanced armature). Current through the coil will inject flux into the armature, setting it in motion. A drive pin connected to the armature on one end moves the membrane on the other end producing sound.

 

 

 

Maxwell Force

Coil injects flux in armature

Unbalanced flux in gaps results in net force

Force displaces armature & membrane (F~FUp2 – FLow2)

  • The coil receives electronic signals
  • Coils injects flux into the armature which starts to vibrate in the magnetic field
  • Vibration of the armature causes the drive pin to move
  • Movement of the drive pin creates a vibration in the membrane
  • Movement of the membrane pressures the air above the membrane, creating sound pressure
  • Sound pressure is let out through the sound outlet.

Technology Moving Coil (MC) Speaker

Technology Moving Coil Speaker

Lorentz Force

Current through coil ; F = B*I*L

  • The coil receives electronic signals, and is magnetized
  • Sitting in a magnetic field, the coil starts to move (moving coil)
  • Movement of the coil creates a vibration in the membrane
  • Movement of the membrane pressures the air above the membrane, creating sound pressure
  • Sound pressure is let out through the sound outlet.

How do MC speakers work?

  • In this type of design the coil is connected directly to a membrane (moving coil design). The coil is located inside a magnetic field and moves when current is applied to it.