96kHz versus 41.1kHz

  • Thread starter Thread starter ecktronic
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cello_pudding said:
with mics that only record up to 20K and speakers that only play up to 20k...not a whole lot.
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LOL Do you really believe that your mics and speakers can only work in the 20hz-20khz range?
 
hmmm...i always thought those things were telling the truth

i just plugged in my mxl990 991 and sm57, ran my sig generator at 20k and 22k.

on speakers that are only supposed to go up to 20k.

i cranked the preamps on my onyx 400f, but every mic played the freq when i listened back.

when i ran over 20k though...the fan on the power to my monitors started sped up. haha. i'm guessing 20k is just a recommended maximum

but still...if you know the nyquist theorem...i'm still recording and playing frequencies up to 20.5k at 44.1.

i decided today that i'm going to record at 44.1/24 bit then dither down to 16 for final bounces.

but i've been thinking about just staying at 44.1/16 so there's no difference between the final product, but i can always but a dither plugin on my master fader.
 
actually I think most mics and speakers will go above 20kHz...but I think that manufacturers only show that as the maximum in the specs because most mics start to slope off in response before 20kHz and it probably slopes off rather quickly after that. So the theoretical, practical use of a microphone is what is mentioned in the specs...and that's usually listed at 20-20kHz...meaning "you should record material between these frequencies with this mic, frequencies outside these limits won't be faithfully reproduced."

But then again, I'm just assuming. Assuming that there isn't a quick brickwall filter limiting anything above 20Khz.
However, I think when selecting your sample rate frequency you also have to take into account what frequencies you are recording. For example, with piano the highest note is 4,186Hz (C8). It's harmonics are at 8,372Hz, 12558, and on up until it reaches 20,930Hz which would be just below the Nyquist frequency...this would be its 5th harmonic. Middle C (C4) would be approaching it's 86th harmonic at this frequency....where most notes in music lie.
So with respect to the arguement over the Nyquist frequency and why you should record at a higher sample rate simply to capture those higher frequencies that help the timbre....{{shrugs}}...
 
still...if you think about how much timbre is going to be added.

think about it as a s/n ratio. that +20K "noise" is going to be so faint, though existing, will be soooo slight. human ears don't go much past 22.
 
wow..i just topped out at around 23980. it was soooo hi.

at 23981 i heard the digital click from turning the sign wave on, but i didn't hear anything more.
 
I just asked my friend spot , and he's dissapointed that mic's roll off at 20Khz.
In his opinion, that's to soon for realistic sound reproduction. :D
 
When the kids are done playing, they might want to read the Lavry article, or the thread linked where I did an experiment based on that theory. Frequencies significantly below the Nyquist level are attenuated due to filter behavior.
 
mshilarious said:
When the kids are done playing, they might want to read the Lavry article, or the thread linked where I did an experiment based on that theory. Frequencies significantly below the Nyquist level are attenuated due to filter behavior.
Click to expand...


anti-alias filters; correct?
 
Usually, the goal of mics and speaker system (monitors) is to somewhat faithfully represent the AUDIBLE frequency range of the human ear. This means, with little to no phase shift (distortion).

So, you will see mics rated up to 15Khz, etc...but that only means it will pick up 15khz with little to no phase shift. It WILL pick up frequencies above 15khz, but the higher you go, the more phase shift there will be.

Same with tweaters.
 
cello_pudding said:
wow..i just topped out at around 23980. it was soooo hi.

at 23981 i heard the digital click from turning the sign wave on, but i didn't hear anything more.
Click to expand...

I doubt you heard anything at 23981. That digital click was probably below the frequency of 23981, that's why you heard it. You didn't hear the sine wave, which means your actual hearing range tops out below 23891.

As has been pointed out, most gear manufacturers state their specs out to 20k. That doesn't mean their mics don't pick up above 20k, or that the speakers don't reproduce sounds above 20k. It means that around 20k the slope of the attentuation becomes greater the higher you go.
 
SonicAlbert said:
I doubt you heard anything at 23981. That digital click was probably below the frequency of 23981, that's why you heard it. You didn't hear the sine wave, which means your actual hearing range tops out below 23891.
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hence the "but i didn't hear anything more."

i believe that would be the monitors range, not my ears. at below that number, the fans were kicking harder than usual, above, they were silent. and the wave was pretty distorted. like there was more than one wave.
 
cello_pudding said:
hence the "but i didn't hear anything more."

i believe that would be the monitors range, not my ears. at below that number, the fans were kicking harder than usual, above, they were silent. and the wave was pretty distorted. like there was more than one wave.
Click to expand...
Why would the fans be kicking in. High frequencies don't take more power to reproduce, they take less. Low frequencies should tax the amps, not highs.
 
i don't know...it does it either way. high or low.
 
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