By faster do you mean lower capacitance? Or higher fT/Current Gain - Bandwidth Product?
I ask since at 10V I think the Cob for 2SC5171 is about 16pF versus 4pF for each MPSA06. So 4x MPSA06 would be about 16pF. And 2SC5171 has higher fT.
So does it mean in this case that one 2SC5171 would not be slower than four parallel MPSA06?
I could certainly put four parallel TO-92 but I would like to understand it better before I do the layout. I have a bunch of genuine 2SC5171/2SA1930 from dead receivers that I used the chassis/heatsink and transformer to make KSA-50 monoblocks. So I am looking for the best place to use them. Otherwise I can just get some MPSA06/MPSA56.
I found a couple Spice models for 2SC5171/2SA1930 but I don't know if I can trust them. One had quite a few default looking values.
I also have some leftover TTC004B (12pF Cob) and TTA004B. I have not found the BD139/BD140 Cob yet.