And strange that 0 Volt DC over a coil resulting in 0 Ampere current are intelligently deducted as this:
Well, since your claim was that your speakers "work" at DC and others don't, and since a simple experiment shows that ordinary drivers indeed do, I have no idea of why you now claim that DC means zero current. Maybe you really do need to find a more gullible audience.
Hadn't tried a Windows machine.
Seems MS protects stuff only from their own users but not from people using Macs.
If it wouldn't be MS I'd think that'd be a bit weird.
Sorry for the OT!
I think you as normal create some internal ideas in your head that for others may look OK and close enough to the truth, but what you do are tweaking by stating "at" instead of "from", "down to"..
Thus you can continue with your regime.
As I wrote: If you apply 0.001Hz the cone will move in and out to the full xmax with my drivers.
Then I wrote: Ordinary drivers will when you put DC voltage on them start the movement, but then be pulled back to near the center.
Maybe DC or 0Hz are what creates you "problem" as a kind of definition issue.
However I see that I should have written "nearer the center" instead of "near the center".
I think I vaguely get the jist of what you are trying to say, if a voice coil or electrostatic diaphragm was suspended with no "stretch" or I gather very weak holding or restoring force of the suspension over a certain region something very good happens (DC response?). In the case of the electrostatic you are correct the diaphragm simply moves till it shorts to the stator, not good. As DF96 tried to explain DC response is not simply moving to a position and staying there accousticly it is a change in local barometric pressure which can only be maintained by sealing off perfectly the local environment on each side of the transducer or at least the listening side.
A voice coil OTOH in the limit simply leaves the gap, no more force, no more motion.
EDIT - I see maybe the confusion is even more fundamental, I can take a lab oscillator that goes down to .001Hz and connect it to the driver out of any old computer speaker and it goes back and forth about the same amount at any low frequency I have done it many times. You just can't have AC coupling anywhere in the path.
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But this is demonstrably untrue.
If you have no restoring force, then a DC voltage (or 0 Hz, if you prefer) will cause a constant acceleration. That means that the cone will fly out of the room- or as a practical matter, run out of voice coil. If there is a restoring force, then the DC voltage will cause the cone to displace- and stay there. The displacement will depend on the point of equality of the BLxI force and the restoring force as a function of displacement.
I don't know if this (true) episode counts as "snake oil" theory. If it doesn't, the moderator is (of course) free to rid the world of it. Usually snake oil theories do not really affect the reality, but some snake oil theories may actually prove disastrous.
We all know that power amplifier need current - lots of it, and cables and wires - no matter how short - do of course obstruct the free flow of music. Especially Class-A amplifier devour vast amounts of current. Once I repaired a very ambitious Class-A amp: One of the channels had completely melted down. The output power transistors and emitter resistors had all but evaporated. The PCB was barely intact. One thing struck me though: The fuses were severely intact. On closer inspection the reason became clear: Somebody had gone to great lengths to improve the power supply to the amp: He had carefully disassembled the fuses, removed the fusewires and replaced them with a length of 1.5mm2 installation cable - probably in the interest of sublime sound.
We all know that power amplifier need current - lots of it, and cables and wires - no matter how short - do of course obstruct the free flow of music. Especially Class-A amplifier devour vast amounts of current. Once I repaired a very ambitious Class-A amp: One of the channels had completely melted down. The output power transistors and emitter resistors had all but evaporated. The PCB was barely intact. One thing struck me though: The fuses were severely intact. On closer inspection the reason became clear: Somebody had gone to great lengths to improve the power supply to the amp: He had carefully disassembled the fuses, removed the fusewires and replaced them with a length of 1.5mm2 installation cable - probably in the interest of sublime sound.
Yes. That is why the true audiophile will insist on direct to disc mechanical recording: the shortest wire is no wire at all!Klarskov said:
This is the fundamental law in your reasoning.
Drivers with a DC offset will move in or out and stay there untill the voltage is removed.
The spider may have something to do with it...
Nonetheless, Paul is right, even in a theoretical unlimited voice coil case, there will be a terminal velocity.
Nonetheless, Paul is right, even in a theoretical unlimited voice coil case, there will be a terminal velocity.
there won't be a terminal velocity. the speaker will move to a position and stay there, until the amp gives out or the voice coil insulation melts.
Note the "even in a theoretical unlimited voice coil case" qualification.
In any case, we agree- the claim that DC applied to a driver will not sustain displacement of a voice coil/diaphragm is utter nonsense.
In any case, we agree- the claim that DC applied to a driver will not sustain displacement of a voice coil/diaphragm is utter nonsense.
even in a theoretical infinite voice coil, there is a spider and driver surround, so even then it would just move to a position and stay there.
if, however, the voice coil is infinite and there is no spider nor a driver surround... we're no longer talking about a speaker driver, are we?
if, however, the voice coil is infinite and there is no spider nor a driver surround... we're no longer talking about a speaker driver, are we?
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