Pf 99

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Hi,

On Andrea Ciuffoli's PF site, they said that

"
The input impedance is 47KOhm/1450pF and its resistive value can be adjusted by a pretty wide range, just using a different input resistance.

The input capacitance, 1450pF, seems to be very high. Please note that a gain stage with a 1000 Ohm output resistance gives a > 100 KHz cutoff frequency.

"

Do they have any problem when use PF 99 with 2A3 pre-tube?

Do we have any way to reduce input impedance and capacitance?

Thanks,
CMP.
 
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