I seem to recall something about as frequency decreases it approaches DC. So a speaker could never produce a zero hertz. It would just remain still and not produce sound and possibly burn out?
Zero means no cone/diaphragm movement, so there is no "frequency" - "zero" and "hertz" are by definition mutually exclusive.
jaberwocky6669 said:
D.C. puts loudspeakers under pressure?
Sorry .... bad joke ..... I hang my head in shame.
zero is nothing and means nothing! So, why should nothing kill a speaker? 😕 
oh dear what a funny tread! 😀
Hatti 😎
oh dear what a funny tread! 😀
Hatti 😎
Since DC is electrons flowing continuously in one direction, wouldn't it push the cone out (or pull it in depending on polarity) and just leave it there?
That's what happens when you hook up a low voltage battery to a driver to test the polarity of the terminals.
The higher the voltage, the more forceful the motion would be (in one direction), and eventually the coil would heat up if there was enough current flow. The wire's pretty thin on most speakers, so I suppose it wouldn't take much DC current to fry a voice coil.
That's what happens when you hook up a low voltage battery to a driver to test the polarity of the terminals.
The higher the voltage, the more forceful the motion would be (in one direction), and eventually the coil would heat up if there was enough current flow. The wire's pretty thin on most speakers, so I suppose it wouldn't take much DC current to fry a voice coil.
Well,
I used to run motion control equipment for stage. The motors were 3 phase AC. The speed of the motor was determined by the frequency applied. Higher frequency, faster spin. The 3 phase AC was generated by a motor controller board.
The board could run all the way down to "Zero Hz", in other words, DC. The DC was used as a brake for the motors. Worked great.
I used to run motion control equipment for stage. The motors were 3 phase AC. The speed of the motor was determined by the frequency applied. Higher frequency, faster spin. The 3 phase AC was generated by a motor controller board.
The board could run all the way down to "Zero Hz", in other words, DC. The DC was used as a brake for the motors. Worked great.
DC or "zero hertz" component is what started long long ago and will last forever. Spectrum is, well, and integral transformation from minus infinity to plus infinity... from times of guys like Bell or de Forest has been just a moment, several nHz or so...
What electrons what voice coils?
DC? Hell no!
What electrons what voice coils?
DC? Hell no!
Actually, it was proabably a variable frequency drive you were working with. They use pulse width modulation to change the frequency of the AC going to the motor to alter the speed. They save a lot of energy that way by not having to alter the voltage to change the speed. They're really cool (but very noisy) devices.
As far as DC and loudspeaker drivers is concerned, the nearest analogy would be a fan, since sound is created by a loudspeaker moving back and forth (AC) which causes excursion (forward) and rarefication (backward) as the electrons change direction. If a loudspeaker driver were able to use DC, it'd just keep travelling forward or backward continuously if it weren't for the spider holding the coil in place. So the fan blowing in your face would be positive polarity, and reversing the direction of the fan would be the equivalent of reversing the polarity. There is no equivalent "sound" because sound is a waveform and DC is the absence of a waveform.
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