Chop shop BJT transistor

[almondcity]

I recently built one of these pretty much to stock with the only difference being this final BJT I used a 2n3904 in place of the 2n2222, figuring it wouldn't make much difference. However, it ended up having much less gain than another one I built with the 2n2222. How critical is this part or was it just some bad jfets?

 

[owlexifry]

difference being this final BJT I used a 2n3904 in place of the 2n2222, figuring it wouldn't make much difference. However, it ended up having much less gain than another one I built with the 2n2222. How critical is this part or was it just some bad jfets?

shouldn't really make much difference as Q3 is mostly an output buffer

the trimpot settings and JFET selection would have a greater impact IMO