Clipping does raise RMS level. But there's no inherent DC in a clipped waveform because it is a changing waveform within the time window of concern here.
Remember that RMS (heating value) includes time also. In DC, it's heating value is it's voltage, which is also it's peak voltage. In AC, any waveform from sine to square, it's Peak value is the highest, it's RMS is always lower than peak. And it's RMS depends on the wave form. Even the RMS value of a square wave is not it's peak value, in fact, they are about 7dB apart.
Here's what clipping "looks" like. The light green is the original sine wave, the blue sine wave has been severely clipped. The amount of clipping represented here (6dB) would be simply unlistenable for actual audio. The RMS value of the clipped wave is more than 8dB below it's peak value.
DC would be a straight line, with RMS and peak being equal, and with no changes.
DC would be a straight line, with RMS and peak being equal, and with no changes.
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in an unclipped signal the coil (and cone) is moving back and forth smoothly the energy supplied is producing motion what we want i think, in the clipped scenario motion is truncated where's the energy going?
after a contemplation scotch i also want to ask if a clipped sine is not dc then how are switch mode supplies possible are they not just a summation of square wave pulses?
The answer to both of the above is a low pass filter. What comes out of the woofer, acoustically, is significantly rounded off due to the low pass filtering action of the driver itself. In the case of a switch mode supply, you sum the pulses and pass it through a low pass filter to clean up any residual high frequency ripple.
At infinite frequency inductance of the coil does dominate. But what you really have is a lossy motor driving a parallel resonant mechanical system. The low pass portion of that dominated by it the mass of the coil and cone (and air column if horn loaded). That tends to resist quick changes like an inductor, the cone doesn’t stop on a dime, which is why the sound out of the woofer doesn’t have all the buzzy high harmonics. Those would get fed to the tweeter, which can respond rapidly enough to the sharp edges of the waveform. But ultimately, they have a low pass action too - just up a couple of octaves higher. This is where people get the idea that clipping damages tweeters - because of “extra” high frequency content. But in reality those components are a drop in the bucket compared to the general average power increase.
well sorry for the sidebar to the thread.
with respect to the original topic and from my experience with compressor and limiters their useful tools but like any tool can be misused and create their own set of problems
with respect to the original topic and from my experience with compressor and limiters their useful tools but like any tool can be misused and create their own set of problems
True, but one other important point concerning that specific thing is that analog and digital limiters don't behave the same. An analog limiter operates in linear time and can only compress the signal while a digital limiter is capable of looking ahead in time(via data buffering) and can use signal tracking gain reduction so that the shape of the signal doesn't change at the threshold of limiting, it doesn't compress or get clipped it just stops getting larger.
By definition, with no cone motion you must be applying DC. In that case, the speaker will appear as a resistor with resistance Re, as determined in the T/S equations.
Chris
Definition is incomplete.
Zero voltage is not DC because there is no current flow. And no cone motion results.
Zero voltage, but connected to a low Z source/load also results in no cone motion, yet if cone motion is introduced mechanically, an AC current flows. Cone motion is damped by the load.
No cone motion AND applied DC does not occur in a normal audio application.
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