PNP LTP vs NPN LTP

[Mosquito]

Hi, In a lot of simulated circuits (restricted to the LTP input, three stage amp genre) I observed that - every other thing being equal - the ones with NPN I/S, and consequently, PNP Vas, perform slightly better than the PNP I/S counterpart.
Not sure if such thing exist in real life circuits, I'm not equipped to detect tiny differences in THD. Is this a common observed phenomen, or only a simulation "mirage" ?
Someone experienced the same thing?
Cheers
J.

 

[sreten]

Hi,

Generally PNP is preferred in the input LTP due
to noise considerations, thus giving a NPN Vas,
which should have higher Ft than a PNP device.

rgds, sreten.

 

[AndrewT]

I would expect that the slightly quieter PNP LTP combined with the slightly better performance NPN VAS, that this arrangement will work slightly better than an NPN LTP.

 

[Mosquito]

"...combined with the slightly better performance NPN VAS, that this arrangement will work slightly better than an NPN LTP.

Ok then, this is convincing enough argument to follow the PNP i/s path in real life circuits, whenever possible