[LAD] random curiosity

[Arnold Krille]

Hi,

On Tuesday 26 January 2010 13:33:52 Gabriel M. Beddingfield wrote:
> On Tue, 26 Jan 2010, Arnold Krille wrote:
> > I don't (yet) get the reason for doing this. If the global seed is
> > initiated with time() it is the same as if each notes seed is initiated
> > with time(), the
> 
> *Is* each note being seeded with time()??
> 
> I got the impression that the seeds were being saved and
> repeated.  The reason why /that/ might make sense is if the
> PRNG is being used for some kind of modulation effect -- and
> then all the notes would have an identical "sound."

I don't know but this sounds a bit stupid to me. You want the random numbers 
to have differences. Playing the same note again on a real piano or violin 
still produces different sounds each time. So I would expect a synth using 
random numbers for variety to behave the same and not give me exactly the same 
each time I hit that note.

But regardless at how the seeds are initialized, when you use a special seed 
for each note, you are very much effected by correlation of the random numbers. 
When using the same seed for all notes, the access to the seed gets randomized 
as soon as you hit two notes together. Which reduces the effect of bad random 
numbers.

And you can't really use scientific random number generators because you want 
to be fast and have realtime with the synth, so you are bound to have some 
strange effects from the random numbers.

Arnold
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