Whats the frequency range of human ear can detect?

[hebu]

An audio question

What's the frequency range of human ear can detect?
And Does it matter if we pass a 38KHz signal to the speaker?

Thanks,

 

[IanP]

Re: An audio question

The audiable frequency range of human ear is ≈ (20Hz-20kHz).
38kHz is above that range and will not be heard..
Regards,
IanP

 

[hebu]

Re: An audio question

But, will this make pepole uncomfortable?

 

[VVV]

Re: An audio question

No, it will not make people uncomfortable, but it can make dogs and cats uncomfortable.
Do you want to asctually pass a continuous 38kHz tone? Or are you simply referring to the amplifier bandwidth?

 

[flatulent]

Re: An audio question

Speakers are more nonlinear than amplifiers. The 38k will produce IMD products in the speaker. Also in speakers with several drivers, the highest frequency one is usually rated for much lower power than the others. If the 38k is strong enough, it will burn out that driver.

 

[rhesusmonkeyboy]

Re: An audio question

As flatulent stated, if you try to send signals to speakers that are beyond their ability to pass on, they dissipate it as "heat" as I recall correctly, ie not as sound, and that can destroy your speakers.

Which will certainly make someone uncomfortable.

Also, as pointed out, perhaps they'd show up as strange sub-harmonics and mix-products.

Don't fear the reaper.
Don't blow your speaker.

 

[hebu]

Re: An audio question

Anybody know why we should kill the 19KHz pilot in FM radio?

 

[flatulent]

Re: An audio question

Anybody know why we should kill the 19KHz pilot in FM radio?

Even though it is not noticeable by hearing, it still affects people, usually making them grumpy. This effect extends up to a few tens of kHz.

I remember a court case where an employee bombarded his superior with such ultrasonic sound to change his mood. Unfortunately, the mood was for legal action when discovered.

 

[Borber]

Re: An audio question

Pilot tone level is about 10% of max audio signal and is constant. It's no sense to load the speakers and amplifier with useless signal which can because of nonlinearities, produce audioable disturbances in speakers.

 

[hebu]

Re: An audio question

But how large the suppression I should provide?

 

[Borber]

Re: An audio question

FM radio uses audio frequencies up to 15kHz. You may use 15kHz low pass filter or simple series or parallel LC notch for 19kHz. Notch will supress pilot at least 30dB.

 

[hebu]

Re: An audio question

Speakers are more nonlinear than amplifiers. The 38k will produce IMD products in the speaker. Also in speakers with several drivers, the highest frequency one is usually rated for much lower power than the others. If the 38k is strong enough, it will burn out that driver.

Do you think is it enough if I make the power of high frequency component below 30dB than audio signal we required?

 

[throwaway18]

Re: An audio question

A few watts at 20KHz makes my eyes feel like they are vibrating and gives me a headache.