Pulsed DC Transformer with Embedded Magnets

[chrisC]

Let me try and save everyone some time.

You will encounter a perceived increase in sound level with your experiment. You may also see an increase on the SPL meter. So the sound at this frequency will indeed appear to be amplified. I think this was a forgone conclusion by most, but anyhow, what do you conclude from this Observer? Here is a hint : When you blow over an empty coke bottle, and are able to "find" the right frequency and make the bottle resonate with a loud tone, you started out with only a very quiet sound of air passing over the hole. Was the sound amplified?


Acoustic vs. Electric Guitars

Your acoustic guitar is louder than your electric, because the acoustic is far more efficient at converting the mechanical vibration of the strings, to sound pressure waves in the air. There is nothing mysterious about that I trust?

With the same energy imparted to the strings in both cases, the acoustic will sound louder because it converts more of it's input energy to sound pressure waves. This is mainly due to the flexible nature of the sound board, the presence of the resonant cavity, and the Helmholtz Resonator nature of the sound hole. On the other hand, the strings on the electric will vibrate for much longer than those on the acoustic, because more of the energy remains in the strings which sustains the standing wave that was set up in them. Tested properly, this will hold true. It's important to note that the pickups on the electric must be removed for this test to be valid, because the magnetic pull in them heavily damps the string vibration. An amplified piezoelectric microphone could be placed on the electric's body to aid in this test.


On Conversion and Efficiency

The creation of sound is all about converting some source of input energy to sound pressure waves. A classic example is that of an electrical input being converted to the mechanical movement of a loudspeaker. The loudspeaker diaphragm converts this mechanical oscillating movement to longitudinal sound pressure waves in the air.

The acoustic guitar, albeit not thought of as such, is also an energy converter. The energy of a mechanically-plucked string and its ensuing vibration, is also partially converted to sound pressure waves in the air.

Neither "converter" is 100% efficient at doing its job. Often, efficiency diminishes sound "quality" or bandwidth. Resonators are very efficient converters, especially if they are made with high "quality" (Q) factors. However, they sacrifice bandwidth for efficiency. It would seem you can not have the best of both worlds. Resonators are very good at working with single or narrow band frequencies. Such is the case with loudspeaker bass reflex (tuned port) systems. (Note: I recommend you study bass reflex design and how Helmholtz resonators are used to amplify OR absorb acoustic energy at specific frequencies, if you are not already familiar with it. It is quite relevant to this discussion and your notion that these resonant "systems" are free energy.)


Tuning Forks

A tuning fork is a type of resonator. It works well at a single frequency. By the very nature of its construction however, it is a poor energy converter in terms of converting mechanical vibration to sound pressure waves. It is analogous to the electric guitar example. Hint: If you can not hear a tuning fork very well, place the "tail" on a wood surface, or even on your skull, they both make fairly good transducers. 

Two identical tuning forks in sympathetic vibration make each other more efficient at converting their combined mechanical vibrations to sound. A single tuning fork alone creates very little by way of sound pressure waves, and some of the fork's energy is dissipated in internal torsional losses and frictional heat from the air resistance. With a pair of forks placed in the proper mutual plane, they can convert some of that lost frictional energy to sound pressure waves, increasing the overall sound pressure level.

When the first tuning fork is struck, its tines vibrate and create an undulating pressure zone between it and the adjacent tuning fork. These pressure waves are what imparts energy to the second set of tines, and results in 4 tines vibrating vs. two. Sound intensity is increased. Now, imagine this pressure zone between the two inside tines of each fork. The tines co-vibrate due to mutual excitation, but in doing so, they offer more "impedance" to movement (due to the pressure zone) compared to if they were freely oscillating alone. This causes the 4 tines to vibrate for less time than two would in isolation.

As with the acoustic guitar, the result is a louder sound, but for less time. The total energy output is equal to the energy input. The output energy can take several forms, depending on the construction of the "converting" device. Overall, no total energy is gained in the system, even though a perceived amplification may have occurred.


The Test

Why not cut to the chase and create a self-running device?

Actually, I rarely do this, but my proposed test was intentionally flawed. It was a test of your knowledge in a way. I didn't see the correct response however.   Do you know why the test is flawed? Hint: read the above. 

.99

Well done .99. If these clowns understand Physics they will not go round in their merry-go-round arguments. Thanks for your efforts in trying to straighten out these crooked knots!

cheers
chrisC

[chrisC]

How to revive the American Dream
...

Has America lost its edge in scientific progress???

Has America degraded to naysayers and insulters???

@Tseung

If I'm reading you correctly, you came back to live in this country that has 'lost it's edge in scientific progress'. I supposed you came back here so your daughter can 'support' you and you will depend on the generous U.S Government for Social Security benefits? Right?  Do you have no shame?

Well, we think you should take the boat back to China or Hong Kong. There, you will find fame and fortune. In the U.S stringent proofs are needed to qualify as a real scientific contributor. Fortunately for this great country, we don't have too many clowns in our scientific establishment.

Maybe a lawyer like Obama can help you....

cheers
chrisC

[BEP]

You said it. I didn't.....

    - Remember that the Sound dBs are used to describe relationships of POWER.
    - To find Power Ratio use the formula...   L_Db = 10log₁₀(P2/P1)

Which scale and time weighting will be used?

Never mind....  To understand weighting should be to understand what we've been saying all along.

[ltseung888]

Observer Experiment Modified and Simplified

@Observer,

I stared at your repeated diagram last night.  I realized that I do not need to spend the US$200 and still get the conclusive result.

Your diagram is modified as shown.  Instead of the speaker, I can use the tuning fork to excite (sympathetic vibrate) the adjustable tube.  It is clear that at the correct resonance frequency, the sound produced by the tuning fork and the air in the tube will be much louder and lasts longer than that by the tuning fork alone.

The sound detecting device (video camera, decibel meter, oscilloscope etc) can be at a fixed distance away.  The tuning fork can be brought slowly to the mouth of the tube previously adjusted for resonance.  I am absolutely certain of the experimental result.  The resulting sound will be louder and lasts longer.

There may be different “hypothesis" on why the resulting sound is louder and lasts longer.

The Tseung hypothesis that additional energy from the environment is brought in is scientifically acceptable.  The total sound energy of the system (tuning fork and tube of air) is more than that of the tuning fork alone. 

@Observer, thank you for the repeated post.  I would have missed the significance if the diagram were posted only once.

May be this is the way intended by the Almighty.  Let us stand on the shoulders of one another.

[chrisC]

..
The Tseung hypothesis that additional energy from the environment is brought in is scientifically acceptable.  ...

Sure it is ..... by clowns only! You're a shameless circus act, Mr. Tseung

cheers
chrisC