Not think; fact.
Alternating current (audio) supplied to the loudspeaker creates sound waves in the following way: a current in the coil creates an electromagnetic field. The electromagnetic field interacts with the permanent magnet, generating a force which pushes the cone outwards or inwards depending on polarity. The current is made to flow in the opposite direction.
Alternating current (audio) supplied to the loudspeaker creates sound waves in the following way: a current in the coil creates an electromagnetic field. The electromagnetic field interacts with the permanent magnet, generating a force which pushes the cone outwards or inwards depending on polarity. The current is made to flow in the opposite direction.
Yeah, any vibrating object will introduce pressure variation into a medium (air), which make ear drum vibrate and magically turn the vibrations to electric signal for the brain to cipher it as sensation of sound. Speakers get to vibrate with the help of electromagnetic phenomenon, which is very convenient, as JonSnell Electronic stated.
Sorry but I've gotta troll some more ways to make a driver produce sound: Speak to a driver, you can measure sound from the terminals (it is a microphone!). Put another driver behind, sharing same enclosure, now there is sound produced /to the outside) by the other driver as well! One can make speaker move by sound, which is kind of moot but demonstrates that (some) microphones work like speaker drivers, but in reverse! There are other transducer technology used in speakers as well as in microphones, like ribbons. Also, you can hear lightning ripping the air, whales sing while diving etc. Sound is just pressure variation. Have fun on your journey to diyaudio!
Sorry but I've gotta troll some more ways to make a driver produce sound: Speak to a driver, you can measure sound from the terminals (it is a microphone!). Put another driver behind, sharing same enclosure, now there is sound produced /to the outside) by the other driver as well! One can make speaker move by sound, which is kind of moot but demonstrates that (some) microphones work like speaker drivers, but in reverse! There are other transducer technology used in speakers as well as in microphones, like ribbons. Also, you can hear lightning ripping the air, whales sing while diving etc. Sound is just pressure variation. Have fun on your journey to diyaudio!
If a sound source (music) through an amp connected to any coil, and a permanent magnet is brought near it, the coil starts vibrating and some sort of music can be heard. (A screwdriver also makes sound, btw.)
If you put the coil into the vent between the pole piece and the permanent magnet, and block it from falling out with suspension (spider), that suspension would give sound when connected to a source (together with the coil). If you then connect the cone to the coil, the sound is much nicer than it was with only the suspension. When the cone is connected to the pliable surround and that to the basket, sound gets better, much easier on the ears. Now, the cone pushes and pulls the air mass in front of it and the back. So, which part of the (full range) driver that makes the sound?
At a given moment, (a millisecond) hundreds of instruments play, some even sing, and all that comes through the “driver.” At a given moment, only a specific number of amperes go through the coil. How does one to-and-fro movement give out so many sounds, at a given moment? Is it only the to-and-fro movement of the air by the cone that gives out so many different gammas of sounds?
The question is still; the cone pushing and pulling the mass of air in front of the cone along its axis makes sound, or something else?
Have a look at most full range drivers.
If you put the coil into the vent between the pole piece and the permanent magnet, and block it from falling out with suspension (spider), that suspension would give sound when connected to a source (together with the coil). If you then connect the cone to the coil, the sound is much nicer than it was with only the suspension. When the cone is connected to the pliable surround and that to the basket, sound gets better, much easier on the ears. Now, the cone pushes and pulls the air mass in front of it and the back. So, which part of the (full range) driver that makes the sound?
At a given moment, (a millisecond) hundreds of instruments play, some even sing, and all that comes through the “driver.” At a given moment, only a specific number of amperes go through the coil. How does one to-and-fro movement give out so many sounds, at a given moment? Is it only the to-and-fro movement of the air by the cone that gives out so many different gammas of sounds?
The question is still; the cone pushing and pulling the mass of air in front of the cone along its axis makes sound, or something else?
Have a look at most full range drivers.
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Sound is superimposed "one" wave. The higher frequencies are riding on the lower ones. Sound is propagated by pressure variation. Driver cone moves according to the signal (within its ability to follow the given signal) causing air pressure to increase or decrease depending which way the movement is. This pressure variation then propagates at the speed of sound. The speaker doesn't know how many instruments there is playing. In fact you could play all the records in the world at the same time and the speaker would play it (within its ability to fllow the signal). But it would sound pretty much like a white noise. Have fun
Sound is superimposed "one" wave. The higher frequencies are riding on the lower ones. Sound is propagated by pressure variation. Driver cone moves according to the signal (within its ability to follow the given signal) causing air pressure to increase or decrease depending which way the movement is. This pressure variation then propagates at the speed of sound. The speaker doesn't know how many instruments there is playing. In fact you could play all the records in the world at the same time and the speaker would play it (within its ability to fllow the signal). But it would sound pretty much like a white noise. Have fun
Are you talking Physics, btw?
I went to university many years ago so yeah, some. Forgot most of it though. It is kind of difficult to know what the reader level is, so trying to balance between easy to grasp terms and actual terms not to talk ******** but still be understandable by most. Just having fun here. Avoiding conflict, which is the most difficult in the internet forums
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I understood that, and that you haven't studied Physics. So, how about looking at most of the full range drivers, and ponder why they look quite different than others. It might help carefully looking at any driver you have, when it is working. Watch the cone carefully, and/or touch the cone with your finger along its surface, from the bottom upwards.
Yes, but it's correct. One could ask the same question as how can all those instruments play along one piece of wire... or how can you listen to two people at once with only one set of eardrums. The waves can co-exist, and even though the result comes out at an average of them all, it still works.
This is true.
But, what I am trying to say is that there are other movements of the driver parts that make vibrations, and at different angles than the plane parallel to the movements of the coil. In other words, there are vibrations going along the cone surface radially, considering it is the main element that creates sound, and that those vibrations, creates sound waves with the most intensity at 90 degrees to the cone surface at a given point (or circle). Every one of them are of other modulation. On full range drivers, the manufacturers usually add extra cones, balls and so forth.
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I've studied enough physics that I know approximately what the eye can see, which is not much. Senses are mandatory for survival but they are poor instruments to study singular molecules or celestial objects. Wrong scale. Eyes cannot even see the cone move much above subwoofer frequencies. You can see the envelope where within the cone moves but the actual movement is not seen. One can make a driver cone look like whatever, performance varies accordingly. Performance, and compromises the performance needs, are defined by the designer/manufacturer. Alright, coffee break over
Edit: yeah the whizzer cones and stuff try to improve high frequency performance of such large driver (cone area). Large cones go through different kinds of resonances, modes, which impart the sound of the cone. Modes are dictated by dimensions and material(s) of the moving parts. Driver cones are "rigid" or, pistonic as it is said, only over limited bandwidth where it perfectly follows what the voice coil is doing but above that different parts of the cone can move in different directions, all of the cone is not following what the voice coil is doing. Physics come into play, smaller things are better at producing shorter sound waves (higher frequency), modes are higher, mass is less, lobes come higher etc. Fullrange drivers are a try to cheat physics (in terms of "optimal audio reproduction"). Ah, well optimal audio reproduction is a poor term since is is subjective to every audio enthusiast. Anyway, I'm out.
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@chdsl
On one hand, pressure in front of the cone can spread all around. In other cases, differing movements of each part of the cone may fight each other. In other cases it may affect only parts of the directivity.
The full range twin cone design considers that a smaller cone section has a smaller mass. It also considers that a smaller cone has a wider directivity to smaller waves.
On one hand, pressure in front of the cone can spread all around. In other cases, differing movements of each part of the cone may fight each other. In other cases it may affect only parts of the directivity.
The full range twin cone design considers that a smaller cone section has a smaller mass. It also considers that a smaller cone has a wider directivity to smaller waves.
Great conversation, yet pretty difficult for me to wrap my mind around. For a somewhat related example of what sound waves can do to a nearby medium, this video shows the effect on water. Now I need to think of this in terms of air affecting my ears. But the point of how many instruments can be conveyed over a soundwave and make the speaker reproduce them so accurately is still at the outer reaches of my comprehension.
Our senses are definitely limited to what we need, and seeing a speaker cone move resulting in a 40 piece orchestra is beyond what we need.
Amazing Water & Sound Experiment #2 - YouTube
Our senses are definitely limited to what we need, and seeing a speaker cone move resulting in a 40 piece orchestra is beyond what we need.
Amazing Water & Sound Experiment #2 - YouTube
When the somewhat stiffly connected bottom end of the cone moves forward, the rest of the cone (surface) is about to start moving. On the other end, there's a soft connection with the surround. With the quick movements to-and-fro of the coil, cone's bottom end moves faster than the top, and vibrations happen along the cone radially. And, all those vibrations send sound waves of different intensity away from the surface of the cone. Also, the dust cap too is vibrating. Usually the dust cap is curved upwards, so the most intensive radiating would be at 90 degrees to its surface at a given point. Same on the cone, going both ways. Anything that vibrates gives sound, if there is a element for it to travel through.
What'd happen, if we make the cone's inside angle larger and larger until it becomes a flat surface? That too would give sound, sometimes even better than the cone. In the 80s last century most companies made flat speakers, 2-way, 3-way, Phillips, Sony, Technics and others. Today, some company is making the so-called BMR drivers.
Cone drivers look nicer, we are used to them. When they have additional ribs on the surface, cones and domes in the middle, they look even nicer. But, the manufacturers won't talk about vibrations of the cone or those surfaces. Maybe, because it is pretty hard to write equations.
Thanks.
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Yeah pretty much, plus they can sell the stuff with colorful marketing sentences, the more exotic the more dollars Performance doesn't necessarily follow, at least not linearly with the price.
I guess flat disk is harder to make rigid without weight penalty and the breakup (first mode) is in lower frequency than with similar circumference cone. Moving mass will limit high frequency extension.
Equations are not needed, in fact they are better avoided, for more sales Breakup can be seen in frequency response and especially in impedance measurement. As always, everything is a compromise, better market with the positives and be silent with the negatives that has to be there to achieve. Instead of "somewhat controlled cone breakup with bumpy directivity index all the way from 1khz to 20khz and small sweet spot" is better marketed as "extended frequency response".
If there was measurably best speaker, that might be single pulsating (not moving back and forth, but inflating and deflating!) point in space which was rigid all the way from 20Hz to 20kHz, but this technology doesn't exists (yet). But still someone would prefer some other technology, which is not wrong, it is just personal preference at the moment.
Performance doesn't necessarily follow, at least not linearly with the price.I guess flat disk is harder to make rigid without weight penalty and the breakup (first mode) is in lower frequency than with similar circumference cone. Moving mass will limit high frequency extension.
Equations are not needed, in fact they are better avoided, for more sales
Breakup can be seen in frequency response and especially in impedance measurement. As always, everything is a compromise, better market with the positives and be silent with the negatives that has to be there to achieve. Instead of "somewhat controlled cone breakup with bumpy directivity index all the way from 1khz to 20khz and small sweet spot" is better marketed as "extended frequency response".If there was measurably best speaker, that might be single pulsating (not moving back and forth, but inflating and deflating!) point in space which was rigid all the way from 20Hz to 20kHz, but this technology doesn't exists (yet). But still someone would prefer some other technology, which is not wrong, it is just personal preference at the moment.
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A cone doesn't always bend significantly during operation. Usually at lower frequencies it operates 'pistonically'. At higher frequencies it can bend in varying patterns, called breakup, with varying effects.
You note correctly that the cone moves along one axis. The directivity is not necessarily related to the shape of the cone. However the resulting wavefront can, in a certain range of frequencies be affected by the shape of the cone.
You note correctly that the cone moves along one axis. The directivity is not necessarily related to the shape of the cone. However the resulting wavefront can, in a certain range of frequencies be affected by the shape of the cone.
Sound pressure is proportional to the cone acceleration.
So you get an alternating voltage signal from a source. Then you do some tricks trying to make the cone move such way that the acceleration is proportional to the voltage signal. If you manage to do this, then the cone radiates sound that is proportional to the voltage signal from the source.
So you get an alternating voltage signal from a source. Then you do some tricks trying to make the cone move such way that the acceleration is proportional to the voltage signal. If you manage to do this, then the cone radiates sound that is proportional to the voltage signal from the source.
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