SV: [sdiy] analog vs digital noise generators

[Scott Gravenhorst]

Each additional bit will double the repeat time and will add
more spectral lumps as well as pushing them closer together.
 For a practical LFSR noise generator that you won't hear
repeating, use 32 or more bits.  Personally, listening to
them, I cannot tell the difference between a good analog
noise generator and a 32 bit LFSR.

One advantage to the LFSR type is that the output is very
high comparatively.  There are also no parts to select for
"best noise characteristics", all LFSRs will sound the same
if the number of bits and feedback taps and clock rate is the
same.


Karl Ekdahl <elektrodwarf at yahoo.se> wrote:
>I just built my first digital noise source and i have
>to say that i really like the way it repeats, other
>than that i don't know....
>
>karl
>
>--- Sumanth Peddamatham <peddamat at gmail.com> skrev:
>
>> hello all,
>> 
>> could someone explain to me the differences between
>> analog and digital
>> noise generators, besides the obvious, of course.
>> :-)
>> 
>> i'm mainly interested in adding more noise sources
>> to my fatman, and
>> stringing together a bunch of shift registers seems
>> to be much more of
>> a pain than biasing a transistor and amping the
>> output.  are there
>> subtleties that i am missing?
>> 
>> sumanth peddamatham
>> 
>> 
>

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