Pumpkin_pre_question

[Josip_Del]

Question about Pumpkin preamp: can it be made with FQP4N20 and FQP7P06 instead IRF-s. Or should I go for IRF

[Zen Mod]

compare voltages , capacitances and xconductance

I presume that IRF's are easy to find , wherever you are ( Cro or abroad ) so I can't see why banging head about ;

if you look for Generg's , you can find that he put Zhoufang's small Toshiba mosfets instead IRF9510

[Josip_Del]

The biggest difference is in xconductance so that I ask FQP has higher xconductance and VGS(th)(4-5)V(FQP4N20) one and the other (3-4)V(FQP7P06)

[Zen Mod]

you'll hardly hear difference because of xconductance difference , because of closed loop operation ; you remember that Pumpie is SUSY .

you can hear difference using Toshibas instead 9510 , because they're less 'switch-like " parts , than IRFs ( transfer curve issue )

lower ones , in CCS position - you can use whatever you have - they're just CCS

[Josip_Del]

thanks for the info

[Zen Mod]

you are welcome