Exchange tips and tricks for the Akai MPC4000
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By Fanu Wed May 29, 2019 9:00 pm
Nyquist theory says we get pristine reproduction for *half* of the chosen sample rate, and we get no aliasing for that range. So, even with our "basic" 44.1K machines we get 22050 Hz pure and clean. That goes way above what we can actually hear. So even 44.1 KHz has some "useless extra" there.
Note that 100% of the digital music we hear and buy is 44.1 kHz and 16-bit.
Now, a machine that uses 96 kHz sample rate can go up to 48 kHz all clean, no aliasing. That's ridiculous, considering that technically speaking the *perfect* human ear can catch 20K tops (adults don't go that high). 96K might probably be great for bats' echolocation sounds, as they happen around 20–200 kHz, ha.

I mix and master every single work day of the week as my job, and I rock 44.1K/24-bit, and it gets converted to 16-bit…and no-one is ever unhappy.
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By CharlesRandolph Thu May 30, 2019 2:06 am
Our ear may only hear from 20hz to 20000 hz, however our body can feel sound at lower and higher frequency.
It's not just higher numbers. Infrasound, Resonant frequency, are no joke. Audio Engineers study the effect of frequencies on everything from water pumps to road noise to sonic weapons.

There's a reason why the governments, limits the frequency of audio devices. (Not A Conspiracy.)
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By CharlesRandolph Thu May 30, 2019 2:36 am
Fanu wrote:Now, a machine that uses 96 kHz sample rate can go up to 48 kHz all clean, no aliasing. That's ridiculous, considering that technically speaking the *perfect* human ear can catch 20K tops (adults don't go that high). 96K might probably be great for bats' echolocation sounds, as they happen around 20–200 kHz, ha.

I mix and master every single work day of the week as my job, and I rock 44.1K/24-bit, and it gets converted to 16-bit…and no-one is ever unhappy.


Why not master at 32 Bit Floating point?
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By Fanu Thu May 30, 2019 8:00 am
CharlesRandolph wrote:
Fanu wrote:Now, a machine that uses 96 kHz sample rate can go up to 48 kHz all clean, no aliasing. That's ridiculous, considering that technically speaking the *perfect* human ear can catch 20K tops (adults don't go that high). 96K might probably be great for bats' echolocation sounds, as they happen around 20–200 kHz, ha.

I mix and master every single work day of the week as my job, and I rock 44.1K/24-bit, and it gets converted to 16-bit…and no-one is ever unhappy.


Why not master at 32 Bit Floating point?


My DAW works at 32-bit floating point of course.
But for release, clients need it 16-bit.
I ask songs/stems at 24-bit, one reason being if I do a vinyl master, that's what plants prefer.
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By CharlesRandolph Thu May 30, 2019 11:12 pm
Fanu wrote:How do we feel 20+ K?


It depends on the person, however our body parts and organs have different resonant frequency. The whole body sitting, will resonant between 5hz and 10 hz. Frequency above 20Khz are Ultrasounds, depending on the power level, it can cause nausea, burning, you can make people hear voices and other things. :nod:

This is why people act a certain way at big concerts, not just drugs/alcohol. But the sheer power of the audio system. vibrating and creating all kinds of frequency. The sounds we hear and don't hear, does something to us mentally, emotionally, and physically.
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By Wormhelmet Fri May 31, 2019 12:55 am
Will 24/96 recording let me create the brown note? That’s all I’m interested in to bring to a large audience. Particularly if the venue is an enclosed small space packed with people.

I don’t care about higher headroom for transient amplitude changes or finer interpolation points attempting to reproduce analog lines

Just want to bring the brown note to masses in a small space
By rabidhamster Thu Jul 04, 2019 4:48 pm
Frequencies can interact with each other in air, so frequencies present in real life from, say a violin for example, that we cant hear, can change the sound of other frequencies we can hear. So the higher sampling rate, allows more original frequencies to be reproduced, if the driver is able, resulting in more natural frequency reproduction in the space. Theres more math to it than I care to understand, and its been a while so I don't have a link, but you can eventually find more information Googling the subject .

Here is a link describing sound interaction to some extent. My understanding is something like frequencies we can't hear can essentially cause constructive or destructive interference to their octaves of frequencies we can hear.
https://courses.lumenlearning.com/boundless-physics/chapter/interactions-with-sound-waves/
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By Lampdog Fri Jul 05, 2019 6:08 pm
rabidhamster wrote:Frequencies can interact with each other in air, so frequencies present in real life from, say a violin for example, that we cant hear, can change the sound of other frequencies we can hear.



This is one of the reason why audio interfaces have rates that high. The math is above our hearing but the frequency interactions are happening. Some collide, some alter others, some influence others.
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By tapedeck Fri Jul 05, 2019 7:48 pm
Lampdog wrote:
rabidhamster wrote:Frequencies can interact with each other in air, so frequencies present in real life from, say a violin for example, that we cant hear, can change the sound of other frequencies we can hear.



This is one of the reason why audio interfaces have rates that high. The math is above our hearing but the frequency interactions are happening. Some collide, some alter others, some influence others.

somebody mentioned it above, and its worth pointing out. there is a weakest link factor that goes on in here. even though an interface can record at 96k doesn't always mean the hardware can achieve that. i have used interfaces that allow you to work at 96k but the hardware itself (the adc) couldn't get that high, so its another case of mere numbers not being entirely reliable.
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By CharlesRandolph Thu Jul 11, 2019 1:25 am
tapedeck wrote:Somebody mentioned it above, and its worth pointing out. there is a weakest link factor that goes on in here. even though an interface can record at 96k doesn't always mean the hardware can achieve that. i have used interfaces that allow you to work at 96k but the hardware itself (the adc) couldn't get that high, so its another case of mere numbers not being entirely reliable.


Sounds like a serious case of false advertising.
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By tapedeck Tue Jul 16, 2019 5:25 pm
CharlesRandolph wrote:
tapedeck wrote:Somebody mentioned it above, and its worth pointing out. there is a weakest link factor that goes on in here. even though an interface can record at 96k doesn't always mean the hardware can achieve that. i have used interfaces that allow you to work at 96k but the hardware itself (the adc) couldn't get that high, so its another case of mere numbers not being entirely reliable.


Sounds like a serious case of false advertising.

not really 'false', just misleading. you can say the device can operate at a high rate, but that doesn't mean all the components do. i do agree though, it aint cool, and we were shocked to discover it. i can't remember which interface it was, but we quit using those for sure.