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Community => General Discussion => Topic started by: arj0n on Tue 18/01/2011 10:28:32

Title: Difference between 41000 48000 and 96000 samples
Post by: arj0n on Tue 18/01/2011 10:28:32
What's the literal difference between 41000 48000 and 96000 samples for the hearing?
Title: Re: Difference between 41000 48000 and 96000 samples
Post by: Unai on Tue 18/01/2011 10:44:25
41000 48000 and 96000 are in Hz (Hertz), that means how many samples per second of audio your file has.

Edit: of course, the more samples you have for each second the better the quality will be :)
Title: Re: Difference between 41000 48000 and 96000 samples
Post by: Calin Leafshade on Tue 18/01/2011 11:06:44
It's not quite as simple as more = better quality. Although in practice thats often what it means.

Sound waves on computers are stored as a series of discrete 'samples' so instead of recording a smooth wave you actually record a series of steps.. much like a digital image is a series of pixels instead of a continuous gradient.

Now, this means that you obviously cant store frequencies which are greater than your sample rate since a single sample cant record the wave going up and coming down again.

What this means in practice is that the maximum frequency you can record is half the sample rate. This is why CDs are encoded at 44khz. Humans can hear up to about 20khz, double that and you get 40khz and then they added a little bit as headroom to give 44khz. There isnt much quality gain past this magic number since we cant hear any frequencies higher so they are lost anyway.

"But Leafshade! DVDs are encoded at 48khz! They must be better!"

DVDs were encoded slightly higher simply to fit in with an earlier digital format and 48khz was chosen to make it difficult for consumer equipment to easily copy the sources (they would need to be resampled which consumer stuff couldnt do at the time). It was just a piracy prevention measure.

There is some argument that ultrasound (anything above 20khz) can affect the listening experience by interacting with other frequencies but as far as i can tell this is bullshit since the vast majority of speakers can only reproduce sounds up to 20k.

Bottom line, anything above 44khz is unnecessary and if you want to go for that retro feel try using 22khz for speech.. it caps any frequecies above 10k and gives it that low frequency muffled sound.

class dismissed.
Title: Re: Difference between 41000 48000 and 96000 samples
Post by: InCreator on Tue 18/01/2011 11:41:54
Perfect thread.
Title: Re: Difference between 41000 48000 and 96000 samples
Post by: arj0n on Tue 18/01/2011 12:27:13
Thanx for that clear explanation Mr. Elephantshittingonface  ;)
Title: Re: Difference between 41000 48000 and 96000 samples
Post by: Leahcim on Tue 18/01/2011 15:05:27
Well that's a useful explanation, thankzz.
Title: Re: Difference between 41000 48000 and 96000 samples
Post by: arj0n on Tue 18/01/2011 15:55:30
And welcome to the AGS-forum DJ Leahcim ;)
Title: Re: Difference between 41000 48000 and 96000 samples
Post by: Knoodn on Wed 19/01/2011 16:01:58
first of all I'm a sound technican. it is my job to hear.

I'm doing a lot of mixing jobs. when I work on tracks I always use 48kHz. my philosophy is (and it's nothing else) that for editing it's important to use a high sample frequency. the very last step is to convert the audio material to 44,1kHz. when I listen then to the result i'm thinking to myself: "ahh, it sounded much better with a higher sample rate." that's only because I know the material (and maybe to legimitate my proceeding).

in fact most people older than 20 years can't hear above 16kHz. Calin is also right with the reproducing by speakers. the upper limits are by 18kHz to 22kHz.

my conclusion: 44,1kHz is a sufficient standard for the hearing.



Title: Re: Difference between 41000 48000 and 96000 samples
Post by: monkey0506 on Thu 20/01/2011 18:32:33
Audiophiles can hear up to like infinity billion KHz. I wish I was one. :=
Title: Re: Difference between 41000 48000 and 96000 samples
Post by: Phemar on Thu 20/01/2011 19:01:03
Quote from: Knoodn on Wed 19/01/2011 16:01:58
in fact most people older than 20 years can't hear above 16kHz.

That's bullshit. I'm a sound engineer as well. Yes hearing does decrease with age but you should be able to hear at least up to 19khz until your late twenties. I can hear up to 21khz and even I'll admit I haven't done a very good job of protecting my hearing. Your hearing shouldn't degrade that quickly unless you go out clubbing every night or you're a diver or something.
Title: Re: Difference between 41000 48000 and 96000 samples
Post by: zabnat on Fri 21/01/2011 06:40:21
Also note that in addition to sample frequency also sample resolution (http://en.wikipedia.org/wiki/Audio_bit_depth) affects the sound quality. That is how many different values each sample can have.  This is usually measured in bits and maybe the most common resolution is 16-bits (CD quality). Most of us can't hear the difference between 16-bit sound and 24-bit sound, but we usually can hear the difference between 16-bit and 8-bit sound.
Title: Re: Difference between 41000 48000 and 96000 samples
Post by: InCreator on Fri 21/01/2011 08:14:23
Quote from: Knoodn on Wed 19/01/2011 16:01:58
in fact most people older than 20 years can't hear above 16kHz. Calin is also right with the reproducing by speakers. the upper limits are by 18kHz to 22kHz.

So, technically, I could take a track, use equalizer to bandstop out all sound to 16KHz or so and see if I hear anything?
Or am I getting this wrong? If it's typical 44000 track, there's no "surplus" sound anyway?

EDIT; Just tested it, last hithat heard (barely) at 16737Hz. But sounds at such frequency, I'm glad I don't hear them. Hearing better means basically worse headache when listening at tv or radio static, amirite?

Lower end for me seems to be 29Hz. So much for sweet, sweet bass.
Title: Re: Difference between 41000 48000 and 96000 samples
Post by: Snarky on Fri 21/01/2011 17:40:45
But as others have pointed out already, this also depends on what your speakers can output. So just because you can't tell the difference on your system, that doesn't necessarily mean you can't hear those frequencies.
Title: Re: Difference between 41000 48000 and 96000 samples
Post by: Calin Leafshade on Fri 21/01/2011 17:46:21
no, most speakers can reliably output signals up to 20khz with little problem, even little pc speakers. It's low frequencies that are the problem for small speakers.

Using an eq to cut everything above a certain frequency is not a good way to test either. Songs are very spectrally complex and no eq can infinitely cut at a specific frequency. If you want to test your hearing you need clear tones.

try these: http://www.noiseaddicts.com/2009/03/can-you-hear-this-hearing-test/

I'm ashamed to say that i can only hear up to about 16k and I'm 24.
Title: Re: Difference between 41000 48000 and 96000 samples
Post by: Anian on Fri 21/01/2011 18:11:00
Quote from: Calin Elephantsittingonface on Fri 21/01/2011 17:46:21
I'm ashamed to say that i can only hear up to about 16k andI'm 24.
If it's any comfort, I've recently turned 25 and apparently I can only hear up to 17k. Talk about making me feel old...on the other hand, I think if you hear up to 21k, you're probably bothered by dog whistles.  ;D
Title: Re: Difference between 41000 48000 and 96000 samples
Post by: Phemar on Fri 21/01/2011 18:38:04
Quote from: anian on Fri 21/01/2011 18:11:00
If it's any comfort, I've recently turned 25 and apparently I can only hear up to 17k. Talk about making me feel old...on the other hand, I think if you hear up to 21k, you're probably bothered by dog whistles.  ;D

Let's just say I don't even watch television because that high frequency whining the capacitors or something makes just annoys me way too much.
Title: Re: Difference between 41000 48000 and 96000 samples
Post by: Calin Leafshade on Fri 21/01/2011 18:39:37
You know that high pitched whine you can sometimes hear when its really quiet? Thats your nervous system :p The low pitched one is your circulatory system.
Title: Re: Difference between 41000 48000 and 96000 samples
Post by: Phemar on Fri 21/01/2011 18:42:27
Hahaha. It's actually tinnitus :P
Title: Re: Difference between 41000 48000 and 96000 samples
Post by: LimpingFish on Fri 21/01/2011 18:56:31
I can hear up to 16k at regular levels. If I crank up the volume, I can hear up to 19k. Even with the volume cranked way up, I still can't hear 20k and above.

I ain't worried.
Title: Re: Difference between 41000 48000 and 96000 samples
Post by: DoorKnobHandle on Fri 21/01/2011 18:57:30
I think there might be an issue with volume because I can also only go to 16-17k. Or is there anybody that actually hears more than some clicks and pops when you begin or end the sample at 18-19k on that site?
Title: Re: Difference between 41000 48000 and 96000 samples
Post by: Calin Leafshade on Fri 21/01/2011 19:16:08
the clicks and pops are artifacts from starting and stopping the wave so abruptly.

My spec analyzer picks up the tones just fine, theres nothing wrong with them.
Title: Re: Difference between 41000 48000 and 96000 samples
Post by: InCreator on Fri 21/01/2011 20:54:04
Quote from: Calin Elephantsittingonface on Fri 21/01/2011 17:46:21

Using an eq to cut everything above a certain frequency is not a good way to test either. Songs are very spectrally complex and no eq can infinitely cut at a specific frequency. If you want to test your hearing you need clear tones.


Nay, I used 3xosc in FL Studio and slided sine wave from lowest possible note to highest. Parametric EQ2 shows also exactly in which Hz sound is playing, so I DO know that those frequencies played. But as for my headset, not really sure if it played higher ones.
Title: Re: Difference between 41000 48000 and 96000 samples
Post by: Kweepa on Fri 21/01/2011 20:56:58
I can't hear anything above 15kHz, and the volume drops off quite a lot before that.
Good to hear that this is pretty typical :=