The importance of Kms(X) and BL(x) for mid-ranges

[lrisbo]

are we looking at the same plot 2 in #331?

 

[phase_accurate]

Yes, I guess so !

 

[camplo]

Isnt it impossible not to have amplitude modulation when combining 2 or more frequencies.

The diaphragm can never be in two or more places at once…

 

[AllenB]

Just because you have one signal appearing to ride upon another, doesn't mean you have modulation.

 

[camplo]

How is this possible given that the diaphragm can only be in one place at one time
I think modulation is always there in a complex signal it’s just a matter of can we perceive it or not

 

[daqvin_carter]

More than one tone can exist in a signal without any sort of modualtion happening.
The cone can follow waveforms other than just a sine wave.

 

[camplo]

The new waveform created by combining two different signals is modulated, whether it is perceptible is what matters

7000hz at a set amplitude results in a particular velocity, adding 700hz creates another set of velocity… they must combine, and they are both modulated now

 

[AllenB]

There seems to be a common, and recent misconception that modulation is simply where one signal is being biased by another.. that it's normal zero-crossing point is being moved around by another signal.

 

[camplo]

There will not be 0 percent modulation with multiple tones

 

[DualTriode]

There will not be 0 percent modulation with multiple tones

Is this a a theoretical or simulation True / False Question?

If it is, the answer is False.

 

[camplo]

Here’s something I found

Is Zero Modulation Possible for Multiple Tones?
Short answer: No.
Understanding Modulation
Modulation is the process of changing one wave (the carrier) with the information contained in another (the modulating signal). It's essential for transmitting information over long distances.
Zero modulation would imply no change to the carrier wave, meaning no information would be transferred.
Multiple Tones and Modulation
When you have multiple tones, you essentially have a complex modulating signal. This signal needs to be imprinted onto a carrier wave to be transmitted. Without modulation, this information would be lost.
Potential Misunderstandings
There might be some confusion due to the term "modulation" being used in different contexts:
* Amplitude Modulation (AM), Frequency Modulation (FM), and Phase Modulation (PM): These are specific modulation techniques where the amplitude, frequency, or phase of the carrier wave is varied according to the modulating signal. Zero modulation in this context would indeed mean no information transfer.
* Modulation in a broader sense: In some fields, "modulation" might refer to any change in a signal's characteristics. However, even in this broader sense, zero modulation would still imply no change, and thus, no information transfer.
In conclusion, regardless of the specific context, zero modulation is not feasible for transmitting multiple tones. Some form of modulation is always required to convey the information contained in the signal.

This is addressing modulation in an electrical signal, which can move faster than a diaphragm could ever

 

[hifijim]

I think there is a difference between modulation, and modulation distortion.

 

[DualTriode]

I think there is a difference between modulation, and modulation distortion.

hifijim,

You are right on target.

I was thinking this but had not said it.

We could use some definitions.

I do have a friend that is all about skipping single side band transmissions around the globe.

We are talking audio frequencies here not RF.

Thanks DT

 

[camplo]

Funny how no one chimed to define the diff between modulation and modulation distortion. There is no difference, if we say modulation itself is a distortion. In practicality we are speaking in comparison to a reference signal?

A Sound Reproduction Device with 0 Modulation Distortion: A Theoretical Ideal
Unfortunately, no practical sound reproduction device can achieve 0 modulation distortion.
Modulation distortion is an inherent characteristic of any system that modulates one signal with another. In the case of audio, this modulation occurs within the transducers (speakers, headphones, etc.) as they convert electrical signals into acoustic waves.
While engineers have made significant strides in reducing modulation distortion to negligible levels in high-end equipment, eliminating it entirely is physically impossible. Factors like the materials used, the design of the transducer, and the operating environment all contribute to some degree of distortion.
Theoretical Considerations
To understand why 0 modulation distortion is unattainable, consider these points:
* Non-linearity: All physical systems exhibit some degree of non-linearity. This means that the output is not directly proportional to the input. Even in ideal conditions, this non-linearity introduces distortion.
* Material limitations: The materials used in transducers have inherent properties that affect their ability to reproduce sound accurately. These properties can introduce distortion.
* Energy conversion: Converting electrical energy into acoustic energy is not a perfectly efficient process. Losses occur during this conversion, and these losses can contribute to distortion.
Pursuing Low Distortion
While we cannot achieve 0 modulation distortion, engineers and manufacturers continually strive to minimize it. This is accomplished through:
* Advanced materials: Using materials with superior acoustic properties.
* Optimized transducer design: Careful engineering to reduce non-linearity and improve efficiency.
* Digital signal processing: Applying digital techniques to correct for some types of distortion.
While perfect sound reproduction remains an elusive goal, the pursuit of lower distortion has led to significant improvements in audio quality over the years.

 

[Kwesi]

The simplest one is missing that occurs even within a ideal and linear sound reproduction chain, when a loudspeaker is used that converts mechanical power to acoustical power with a membrane that moves forth and back by principle, and produces at least two tones at the same time: Doppler distortion/modulation.

 

[lrisbo]

Doppler causes FM and what we see is clearly dominated by AM

 

[454Casull]

Funny how no one chimed to define the diff between modulation and modulation distortion. There is no difference, if we say modulation itself is a distortion. In practicality we are speaking in comparison to a reference signal?

Are we saying that any waveform that made up of multiple summed waveforms must inherently be distorted?

 

[lrisbo]

depends on the input to the system. If the output contains more frequency components than the input then yes. Linear systems respond at the same frequencies as the input.

 

[TNT]

If the output contains more frequency components than the input then yes.

Well, thats the definition of distortion so no big surprise ;-D

If the summing mechanism is perfectly linear, there should be no IM - right!?

//

 

[454Casull]

That's what's confusing me, like I'm hearing that anything that isn't a sine wave must contain distortion and cannot be "fixed" (as if there were anything wrong with it in the first place)