As far as I can tell those two diodes are normally either non conducting or conducting so little they make no difference. The emitter volts of TR102 is only around 350 to 400mv. and that plus the vbe drop does not quite equal two diode drops. Its on a knife edge but I don't think work for setting current in any way in normal operation.
This is about Chrisr3521's problem, and I am hoping to be of help to him in order to solve this.
In no way am attacking him or useful contributions to the discussion by anyone else. I leave it up to him to judge what to do. Your comment about the late JLH in post 47 was provocative and implied your knowledge about audio amplifiers was greater than his, a man who spent a lifetime in the field of electronics. It would have been advisable before making comments to search the internet for information about the man's involvement in the field of electronics.
In no way am attacking him or useful contributions to the discussion by anyone else. I leave it up to him to judge what to do. Your comment about the late JLH in post 47 was provocative and implied your knowledge about audio amplifiers was greater than his, a man who spent a lifetime in the field of electronics. It would have been advisable before making comments to search the internet for information about the man's involvement in the field of electronics.