How I would build a Si FF like circuit

[Gus]

I did a sim of how I would build a Si FF like circuit using a 2n2222 transistor and having a grounded emitter at Q1.
Note how close almost exact it is to a VOX circuit.  Look at R.G.'s site or search for Vox schematics

Note the voltages reported in the sim.
I added the lowpass (C4,R4)I shared years ago on the web.  I don't like the C to B caps.
The BIG FUN is the external bias control(R7) IMO this is the correct place for it not in the collector leg.  Also note some fuzzes had 2K gains.

LAYOUT and wire length matter with a Si circuit like this.

Gus

[mac]

Gus,
I'd use BD175 or BD233-5-7 transistors because they have low gain and low freq transition, much less brighter than BD139, 2n2222 or 2n2369.

mac

[GodSaveMetal]

I made this for my own and have a good taste, BC108/109 metal can one´s:

Used all linear taped pots, and control real, good for SATISFACTION, Rock´n ROLLING!!!