understanding some terms and theory

[Paul Maddox]

John,

>
>Simply... if you play a 64-byte wavetable to generate a 1Hz signal,
>then each step lasts for 1/64 of a second - zipper noise anyone??!
>On the other hand, each step of an 8k wavetable lasts 1/8192 of
>a second.
>

agreed, but then consider this... you need to have a VCO running at 8192 
times the frequency you want, this VCO has to go from say 8kz(1hz audio) 
to say 40khz (5khz audio) dont forget this has gotta be log scale too...

Next if you go for a FULL table (no interpolation) if you have 8192 
samples in a single wave, how many waves in a table, say 1024 for 
clarity (as you suggested clarity as a concern) this gives 8388608 
samples in total.. yes 8Mb, tis is for ONE sound... pratical? this is 
assuming you have 8bit samples if you go for 16 (again clarity) we now 
talking of 16mb of data for one single sound.. anyone care to find 2 low 
cost 8mb eproms? so if you want say 32 tables such as the PPG then we're 
upto 512mb of sample ROM... this ISN'T CHEAP!

A lot of modern synths use PCM, Im unsure how it works but I know it 
uses less space, but in so doing, will also use a lower quality of 
sample..

Its a balancing act, very hard one to get right.

>Hey ho.. I'm writing too much :)
>

nah... I am... :O)

>
>john..
>

Paul Maddox



***************************************************
*  Modulus DIY Web Page ;-                        *
*      www.geocities.com/siliconvalley/park/2707  *
*  E-Mail ;-                                      *
*      Space_banana at hotmail.com                   *
***************************************************


______________________________________________________
Get Your Private, Free Email at http://www.hotmail.com