Speakers w/ Freq Responce above 20kHz

[jacksonbart]

This may be a stupid question, but why do some speakers manufactures quote the frequency response on the high end above 22kHz? I have seen numbers as high as 55kHz, just wondering what the point is? I know you cant hear that high or at least I cant, but wondering if that meant that speakers that where rated at only 40Hz to 20kHz where something less in the top end?

I know people want sub that go sub harmonics, south of 19Hz but is there a corresponding preference for frequency response above that?

Does anyone know if this is a true fact and if it makes a difference in the sound?

I know, I know, listen to them myself, but recently I have heard some KEF (just one example) speakers that had specs above 48kHz. I could not tell.

Just wondering if you think this is a gimmick or whether the manufacturer actually spent time/money getting out put that high out of the tweeter, as opposed to say the RF7. Thanks in advance.

[DrWho]

Mostly it's just marketing...

However, there is some debate as to the psychological effects of frequencies above the audible range. If nothing else, one thing that can be proven is that frequencies above 20kHz can interact with frequencies below 20kHz and cause beat frequencies in the audible range. Even two inaudible frequencies can create an audible beat frequency as well (25kHz and 26kHz create a 1kHz tone).

Now to get back to reality, the mediums on which we record audio don't record information that high (even analog mediums don't handle information very well about 18kHz). CDs can only go up to 22.5kHz. So if your medium isn't requiring your system to play back information in those frequencies, then having a speaker capable of it is complete overkill.

Having a subwoofer that can play 1-10Hz is rather pointless if you have no source material with information that low...the sub will just sit there and do nothing.

[Duke Spinner]

thier Dog's ...

like to play a tune, or two ....

..... ........

[D-MAN]

I've read that some feel that there are harmonics generated by frequencies higher than we can hear that in certain combinations and modes are low enough to actually hear, and these supposedly are "good".

This theoretically makes some sense in that nature does produce them too, like the audible "overtones" and lower harmonics of a cymbal for example. Who knows?

Something to think about, anyway.

DM

[Marvel]

Shhhshh!!! Don't tell Rupert Neve it doesn't matter.

[3dzapper]

"However, there is some debate as to the psychological effects of frequencies above the audible range. If nothing else, one thing that can be proven is that frequencies above 20kHz can interact with frequencies below 20kHz and cause beat frequencies in the audible range. Even two inaudible frequencies can create an audible beat frequency as well (25kHz and 26kHz create a 1kHz tone)."

Isn't that the defination of imtermodulation distortion? I agree whith the good Dr. Marketing plain and simple. Remember, some audiopiles can hear the difference with a jar of rocks.

Rick

[timbley]

I read about a study done in Japan where they had people listen to music with and without the ultrasonic frequencies. They were measuring brain activity, and there was noticeably different brain activity with the higher frequencies present. People didn't comment that it sounded better in any specific way, but did report that they enjoyed the listening session more.

[Shaggy and Scooby]

My personal experience is they sound tinny. This is my main reason I don't like the new synery speakers. They are very bright and can sound harsh. I have heard other speakers that have the 20+k range before the synery's even came out and had drawn the same conclusion. You are inducing a very high frequency noise or vibration into the mix. My very limited education theory is that the vibration of the diaphragm at the higher frequencies starts to have a adverse effect on the lower ones. Causing breakup on the diaphragm itself. Kinda hard to explain but I'm sure this will really spark some replies. I really think if you are trying to get rid of dogs or bats in the neighborhood then its a good idea.

[formica]

I believe the thinking goes that if the tweeter extends well beyond our hearing... it shoiuld be relatively flat at our natural roll off frequency. Obviously there is a lot more to it than the ±3db rating... and alot of it is just marketing

BTW, we should note that most males past 20 will only hear to about 16khz.

Rob

[djk]

" I have seen numbers as high as 55kHz, just wondering what the point is? "

For people that have a problem with roaches?

My hearing on sine waves quits about 13Khz, but I can tell on music if the speaker goes higher than that.

I can't hear the 15Khz from a TV set, but I can sure tell its there when I get my head close.

[ZAKO]

You dont want to get your head close to the TV. The brain waves will distort the picture.

[Spkrdctr]

Generally, it is a bunch of hooey! Most males are lucky to hear above 16kz most of the time. My cat on the other hand likes it.........

Bose has proven that you can have huge amounts of sound information missing and still enjoy the music. I would not recommend it for Klipschophiles, but it can be done. We (humans) are not all that discriminating most of the time. 99% of the time you can have a little clipping and you will never know. But, in the end, having everything the best you can make it, usually does produce amazing sound.

**NEW EDIT*** Whoops! I just realized that I did not tie the above post in to the topic. I meant to add that you need not worry about missing sound reproduction above 20khz. That is my reference to Bose. Good thing I re-read this post. Sheesh! Sometimes I really botch a post now and then......*****

Now about Bose.......