Hi, Saurabh.

   I think this is due to the transistors of output cascade being non identical.
To improve situation make output stage really AB (not B as shown),
if I'm not mistaken (I'm not an EE). Put resistors between bases
of Q11 and Q13 to Vdd and Vss respectively.
  Then R18 need to be adjusted to set current in quiet state.
Better add to R18 a couple of diodes for thermo-compensation.
   I didn't think C4,C6 need to be different. Even maybe one will be enouth.
   How about feeding output cascade with 30v DC(not 15v as shown).
   R13 need to be reduced, as well as quantity of amplifying cascades.

   Good luck.
   Mike (being not an EE).

PS: Why did not use IC?



>Hi,
>
>Can anyone please advise what may cause the negative
>clipping on the output stage? My feeling is a poor pnp
>device? Any better ideas or suggestions? The attachment
>is a word format, if this is inconvenient, I can send
>a pdf or jpg version (let me know).
>
>Thank you (in advance).
>Kind regards,
>Saurabh Sinha

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