The speaker cone is attached to the voice coil and attached with a flexible mounting to the outer ring of the speaker support. A light voice coil is mounted so that it can move freely inside the magnetic field of a strong permanent magnet.
More power is needed in the bass range, making multiple drivers with a crossover a practical necessity for good sound.Īn enormous amount of engineering work has gone into the design of today's dynamic loudspeaker. Speakers have a free-cone resonant frequency which distorts the sound by responding too strongly to frequencies near resonance.
The free cone speaker is very inefficient at producing sound wavelengths longer than the diameter of the speaker. The sound from the back of the speaker cone will tend to cancel the sound from the front, especially for low frequencies. The enclosure is an essential part of sound production because of the following problems with a direct radiating loudspeaker: But you won't - not without a good enclosure. Once you have chosen a good loudspeaker from a reputable manufacturer and paid a good price for it, you might presume that you would get good sound reproduction from it. Some basic ideas about speaker enclosures might help with perspective. This process involves many difficulties, and usually is the most imperfect of the steps in sound reproduction. The loudspeaker involves electromechanical processes where the amplified audio signal must move a cone or other mechanical device to produce sound like the original sound wave. The other stages in sound reproduction are mostly electronic, and the electronic components are highly developed. The loudspeakers are almost always the limiting element on the fidelity of a reproduced sound in either home or theater. This action on the air produces sound that more-or-less reproduces the sound pressure variations of the original signal. The voice coil is attached to and drives the cone of the loudspeaker, which in turn drives the air. Once the amplifier has made the electrical image large enough, it applies it to the voice coils of the loudspeaker, making them vibrate with a pattern that follows the variations of the original signal. Any changes would be perceived as distortions of the sound since the human ear is amazingly sensitive to such changes. Having a "high fidelity" amplifier means that you make it larger without changing any of its properties.
The job of the amplifier is to take that electrical image and make it larger - large enough in power to drive the coils of a loudspeaker. That is, it produces an electrical signal that has the same frequency and harmonic content, and a size that reflects the relative intensity of the sound as it changes. Loudspeakers Dynamic Loudspeaker PrincipleĪ current-carrying wire in a magnetic field experiences a magnetic force perpendicular to the wire.Īn audio signal source such as a microphone or recording produces an electrical "image" of the sound.