Nyquist Theory Explained - Posted on 2015-01-07 by Felix Nieto

Hey Guys

So today we are talking about the Nyquist Theory and what it means for us today. Its a good theory to understand because i know a lot of people always have questions about it and wonder how to impliment it into their work. 

So in a nutshell, the Nyquist theory pretty much says that in order to accurately sample a frequency you need to be able to catch one compression and one rarefaction of each cycle to succesfully convert an analog signal to digital. 

Going deeper into the theory it talks about humans range of hearing (20hz-20khz). That means that the highest number needed to be sampled is 20khz.. Because we have to catch each cycle twice (a compression and rarefraction) then you would need to multiple the rate by 2 (20khz x 2 = 40khz). Granted you probably want to leave a little room for error which is why the minimum sample rate is 44.1

So now that you know a synopsis of how it works you maybe wondering why there are sample rates all the way up to 192khz. Well what these sample rates all is just like what stated above. More samples per cycles of frequencies. So instead of only being able to get one compression and one rarefaction of 20khz, with a sample rate of 192khz you can get almost 5! That means that you are now able to catch more of the amplitute and detail. 

So that my friends is the Nyquist Theory explained. Now im sure some of you may still be wondering why would anyone sample at such a high rate like 192khz? Well thats a good question. One that i cant answer. When you sample at a high rate yes you do get more subtle detail and transients but at the end of the day when you have to convert it to CD quality did you actually gain much more for all those large data files on your hard drive? Only you can find that out for yourself.

Anyways thats all for today friends, and like always,

Go make better mixes and I'll see you on the next one!