what transistors to use?

[prorms]

i dont understand what this part does but i know its inportant
to get this style of poweramp to function correctly
just wondering what transistor that would be a great choice
for this section of the poweramp

[BobEllis]

Do not attempt to build that circuit. See the "100W amp does not work" thread.

If all you are trying to do is learn what that section is supposed to do, you would be better off studying other properly completed designs. The transistors you identify are part of the protection circuit. They can be almost any small signal type, such as MPSA42/92 or BC546/556.

Professor Leach describes how his protection circuit works in his Low TIM amp pages. There is also a thread here about triple slope protection circuit design.