MILLER CAPS ...

[sakis]

OK... many said arround miller caps
been also playing around with various types ...
lets suppose a simple circuit example: the P3A
I would like to have opinions on what type of capacitor will play better ?

i have ceramics blue coloured that are 3KV 100pf
i have Cornell Dubilier mika also 100pf
i have 100 pf /160v styroflex

i probably have or can find other types also...

question is which is better to use and which will sound better from all if we take as a fact that value is 100pf ..

then comes one other question that is critical to me and here i need more help since my theory is bad :

question is how to calculate properly the value of the capcitor if VAS for exampe is BD 140 or MJE15035

thanks in advance
sakis

[wahab]

Originally Posted by sakis

question is how to calculate properly the value of the capcitor if VAS for exampe is BD 140 or MJE15035

Cdom correct value is in function of input stage current capability.

The VAS transistor itself will mandate a value such that Cdom
will have a higher value than the BC junction varying parasistic
capacitance.

Generaly, a low Cob transistor will need a lower value than
devices like BD 140 or MJE15035 , but neverless , 47pf is generaly
an accepted working value for a simple VAS , while 100pF is mandatory
with darlington Vas.