Amplification by concentration...

[Externet]

Is the title right ?

 

 

How do wavefronts increase their amplitude trough a funnel ?

 

The inlet area ratio to the outlet area produces a louder signal, obviously, as these things worked a long ago.

What about the effect of its length - which relates to the angle ?

 

If a soundwave gets amplified entering the wide end and exiting the narrow end; what is the effect in the opposite direction ?

 

 

Is the wide end flaring an empirical/cosmetic shape ?

 

 

[fiveworlds]

A cone creates constructive interference by concentrating the sound waves in a smaller area. In the opposite direction the sound waves are forced to follow a specific direction and cause constructive interference in one direction only.

[Mordred]

A cone creates constructive interference by concentrating the sound waves in a smaller area. In the opposite direction the sound waves are forced to follow a specific direction and cause constructive interference in one direction only.

+1 excellent answer.

[studiot]

Is the title right ?

 

ear horn.jpeg

 

How do wavefronts increase their amplitude trough a funnel ?

 

The inlet area ratio to the outlet area produces a louder signal, obviously, as these things worked a long ago.

What about the effect of its length - which relates to the angle ?

 

If a soundwave gets amplified entering the wide end and exiting the narrow end; what is the effect in the opposite direction ?

 

Victrola.png

 

Is the wide end flaring an empirical/cosmetic shape ?

 

 

 

 

Sorry no,there is no amplification.

For there to be amplification there would have to be energy.power source adding energy to the sound wave.

 

Yes concentration is a good non technical word but I think you know enough electronics to understand the technicalities.

 

Any sort of funnel shape acts as an acoustic transformer in much the same way as a line transformer is used in audio and public address engineering to match the impedance of the line signal to the loudspeaker or the microphone signal to the line.

 

The ear and the gramophone pickup have a higher acoustic impedance, which is (better) matched by the narrow end of the funnel and the free air has a lower acoustic impedance which is better matched at the wider end.

 

The flared shape is the most efficient to reach the optimum diameters smoothly and quickly.

These are known as horns, after musical instruments that also operate on this principle.

[Externet]

Thank you.

Concentration as titled may not be the precise word as suspected; perhaps magnification or as suggested, constructive interference, or some other proper

term.

 

 

A cone creates constructive interference by concentrating the sound waves in a smaller area. In the opposite direction the sound waves are forced to follow a specific direction and cause constructive interference in one direction only.

 

Sound waves are forced to follow a specific direction in both funneled directions. What differs ?

How is the constructive interference isolated/'singled out' in a way that the destructive antinodes in the funnel have no effect ?

 

 

For there to be amplification there would have to be energy.power source adding energy to the sound wave.

OK, agreed for increasing power.

 

Without adding energy, an electrical audio transformer that matches impedances does provide passive amplification of amplitude, at the expense of attenuating its current magnification. The power is nearly sustained except for transformer losses. Please correct.

[KipIngram]

In a lot of systems the loss mechanism goes up with power, so in that sense raising energy density or power level can cause you to lose a larger fraction of the energy before you use it.

[studiot]

Thank you.

Concentration as titled may not be the precise word as suspected; perhaps magnification or as suggested, constructive interference, or some other proper

term.

 

 

 

Sound waves are forced to follow a specific direction in both funneled directions. What differs ?

How is the constructive interference isolated/'singled out' in a way that the destructive antinodes in the funnel have no effect ?

 

 

OK, agreed for increasing power.

 

Without adding energy, an electrical audio transformer that matches impedances does provide passive amplification of amplitude, at the expense of attenuating its current magnification. The power is nearly sustained except for transformer losses. Please correct.

 

 

Concentration is the right word.

 

It is not an interference phenomenon.

If it was then reinforcement would be the right word for constructive interference.

 

It is a simple matter of focusing or collecting or - yes - concentrating all the available power into the region within the horn.

Normally sound would be emitted in all directions.

So if the volume of the horn was 1/16 (typical) of the volume of a sphere then you might expect a concentration of 16 times.

This will not be achieved in practice because of (friction) losses at the surfaces of the horn.

 

You are right that the (electrical) power matching can be better than 90% efficient for an electrical transformer.

A horn will not achieve anything like this 30% being very good indeed.

 

I did not link to any articles on acoustic impedance or horns.

 

I assume you can look these up for yourself, but please ask away any further questions.