YES > but it clearly shows with accurate visual depiction > REAL WORLD RESULTS & OUTCOMES. [ deviation of the original waveform ]
The best speakers I've ever heard were very low mass designs... either planars or the Plasmatronic!
At BAF24, the Plasmatronic was using a pair of Quads as woofers. That was so over the top... it was... FANTASTIC.
If only @Tony Salsich didn't live so far... I think I would be frequent visitor bringing gifts of food and drink to his house.. ;-)
A speaker originally conceptualized by a Physicist!
At BAF24, the Plasmatronic was using a pair of Quads as woofers. That was so over the top... it was... FANTASTIC.
If only @Tony Salsich didn't live so far... I think I would be frequent visitor bringing gifts of food and drink to his house.. ;-)
A speaker originally conceptualized by a Physicist!
That's where your very basic physical misunderstandings start. An applied force moves a mass instantly. It is a similar thing with a signal passing through a low-pass circuit. The output also reacts instantly, without any delay.
If you double the mass and the force, the resulting motion is the same.
So...
... yes, of course.
There is no such thing as INSTANTLY.
I studied Physics, I got a piece of paper that the Wizard of Oz gave me.... trust me, there is NO such thing as INSTANT response. It it were there would be no losses in a speaker motor and no heat would be generated.
Only engineers would claim so...
THINK.... think about what you claimed... how can response be instant? In order to be so, there would be no propagation velocity... THINK about that!
Don't assume that things "are"... think about WHY things might be!
Are you claiming that there is some sort of quantum entanglement driving the speaker motor?
I studied Physics, I got a piece of paper that the Wizard of Oz gave me.... trust me, there is NO such thing as INSTANT response. It it were there would be no losses in a speaker motor and no heat would be generated.
Only engineers would claim so...
THINK.... think about what you claimed... how can response be instant? In order to be so, there would be no propagation velocity... THINK about that!
Don't assume that things "are"... think about WHY things might be!
Are you claiming that there is some sort of quantum entanglement driving the speaker motor?
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YES > but thanks to today's 'powerful' neodymium magnets plus high current amplifiers, we finally have a method to move MASS quite effectively.
There is a difference between a powerful field and a constant field.
The back EMF is a measure that is affected -in part- by the coil's own magnetic field affecting the magnet's would-be-constant field. Effectiveness is an engineering solution to the problem. but it still takes into account more than just the strength of the permanent magnet.
I suppose that the larger the flux of the permanent magnet, the lower the ratio between the coil's field and the magnet's... but this still doesn't solve the problem. Just alleviates it.
I think the best magnet is going to be an active device that can absorb the back EMF generated by the coil... so the speaker doesn't have to absorb it.
And yet, we have the issue of phase shift of the driver... but at least we can solve one of the problems.. and take the amplifier's damping factor out of the way.
The back EMF is a measure that is affected -in part- by the coil's own magnetic field affecting the magnet's would-be-constant field. Effectiveness is an engineering solution to the problem. but it still takes into account more than just the strength of the permanent magnet.
I suppose that the larger the flux of the permanent magnet, the lower the ratio between the coil's field and the magnet's... but this still doesn't solve the problem. Just alleviates it.
I think the best magnet is going to be an active device that can absorb the back EMF generated by the coil... so the speaker doesn't have to absorb it.
And yet, we have the issue of phase shift of the driver... but at least we can solve one of the problems.. and take the amplifier's damping factor out of the way.
INTERESTING 🙂
[ I can understand that super high DF (dead short) of back EMF does actually create an 'internal stress' to the driver ]
[ I can understand that super high DF (dead short) of back EMF does actually create an 'internal stress' to the driver ]
I don't know how absurd a conversation has to become to decide that something is minimum phase - https://en.wikipedia.org/wiki/Minimum_phase
This really is key.
Where is the nonlinearity?
The moment you apply a constant force to a (free) mass a constant acceleration is in effect immediately, a = F/m. The velocity change follows v = a*t, which means it is zero only in the very first infinitesimally small moment but builds up quickly. There is no dead time or anything like that, the movement starts instantly.
Yeah and acoustic sound is the acceleration, not the velocity or displacement, so sound is imminent.
Velocity is the back EMF generator though. Driver has two operating zones: the resonance where mass is cancelled by spring and force goes directly into velocity so the back EMF is exactly opposite phase to excitation and works as damping force. Above resonance, on higher frequencies, at the so called mass controlled region, motor force goes into accelerating the mass and now velocity (backEMF) drags behind the excitation force and does not dampen anymore. Here one could reduce current due to the backEMF somehow, like with a series inductor, because it's not useful and just detrimental, error current basically. On the resonance backEMF is useful, it dampens the resonance.
Please anyone with any questions with it read this article. Just ignore the title as it's all about understanding how the driver works, not the amplifier. It's explained nicely with quite simple math:
https://www.edn.com/loudspeaker-operation-the-superiority-of-current-drive-over-voltage-drive/
Think a weight at the end of a spring hanging from ceiling. Poke the weight with a finger with very little effort and it keeps on going, starts oscillating, resonating at frequency where the spring and mass cancel. Try to shake the weight at some higher frequency, and now you must basically do a lot of work to make it going and keep it going, because the spring doesn't help. So, the discussion here doesn't seem to separate the resonance and what happens above.
Velocity is the back EMF generator though. Driver has two operating zones: the resonance where mass is cancelled by spring and force goes directly into velocity so the back EMF is exactly opposite phase to excitation and works as damping force. Above resonance, on higher frequencies, at the so called mass controlled region, motor force goes into accelerating the mass and now velocity (backEMF) drags behind the excitation force and does not dampen anymore. Here one could reduce current due to the backEMF somehow, like with a series inductor, because it's not useful and just detrimental, error current basically. On the resonance backEMF is useful, it dampens the resonance.
Please anyone with any questions with it read this article. Just ignore the title as it's all about understanding how the driver works, not the amplifier. It's explained nicely with quite simple math:
https://www.edn.com/loudspeaker-operation-the-superiority-of-current-drive-over-voltage-drive/
Think a weight at the end of a spring hanging from ceiling. Poke the weight with a finger with very little effort and it keeps on going, starts oscillating, resonating at frequency where the spring and mass cancel. Try to shake the weight at some higher frequency, and now you must basically do a lot of work to make it going and keep it going, because the spring doesn't help. So, the discussion here doesn't seem to separate the resonance and what happens above.
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More force comes from stronger magnet, which is totally independent from amplifier current - so no more distortion.
You don't have a clue about loudspeakers...
Read about Bl Thiele-Small parameter.
The cone acceleration is always going to follow the applied signal.
And that's what it should do, as sound pressure is created by acceleration.
The only thing a square wave will reveal is bandwith. Equalize two woofers, one with a low mms and one high mms to the same bandwith and roll off, say 30-150 Hz and the SW will be indentical.
I think you are at not using the standard meaning of "move" (displacement or velocity). Acceleration is not itself movement to most reasonable definitions. It creates motion over time, but not instantly.
Few would argue that the analogous situation of applying a voltage across an inductor causes current to flow instantly.
And you don't have a clue about physics, huh?
Forget it... at best you're talking like engineers, not thinking fully what it is that fundamentally happening.
The cone is always accelerating.... but with delay to the applied signal.
And then you got flat panel membranes that have less delay.
Speakers are not always cones, you see.
The sound pressure has little to do with the discussion... except that it will might apply a non linear resistance to the movement of the code.... non linear because compression and rarefaction are different.
^ I changed the wording. Technicians actually know how to make things. Physicists smoke things.
Engineers just think the know everything. The world needs engineers but we just don't want them to run it.
Engineers just think the know everything. The world needs engineers but we just don't want them to run it.