[sdiy] Analog Modeling, with a computer!

[Antti Huovilainen]

On Thu, 15 Sep 2005, Richard Wentk wrote:

> At 21:05 14/09/2005, Antti Huovilainen wrote:
>> I often hear statements like this, but I've yet to see any of them backed 
>> up by hard data (such as a listing with values for a typical poly* 
>> capacitor at audio frequencies). So excuse me, if I remain skeptical.
>
> You'll find the L+ Series R + Leakage R equivalent circuit for capacitors in 
> any decent electronics textbook. It's most applicable to electrolytics, which 
> are light years away from being ideal. But it can also be relevant for other 
> types.

Ok, but what are the _values_ of the parasitic components?
Having parasitic components is one thing. Having such large parasitic 
components that they affect things at audio frequencies is completely 
another.

> It's also easy to check the differences empirically. Breadboard a filter, and 
> try different kinds of capacitors with identical nominal values in the audio 
> chain.

This has the problem that you're varying many other things besides simply 
the parasitic elements. You'd somehow have to find a way to keep all other 
things exactly identical when doing the recordings, otherwise you're not 
measuring what you think you are.

Antti

"No boom today. Boom tomorrow. There's always a boom tomorrow"
   -- Lt. Cmdr. Ivanova