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No sound at all on double-checked superbasic distortion circuit...
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John B:
Probably a good time to think about what you want or expect the circuit to do? I gather it's a distortion circuit, but do you have even a visual idea of what the output waveform should be? Does it essentially clip one half of the waveform?

The way that it is currently biased leaves a lot of variables that would affect the output signal significantly. Resistor tolerances, transistor gain and Vbe due to temp etc..
bob91343:
I suspect the transistor is saturated.  With 68k collector load from 9V we would like a collector current of perhaps 60 microamperes.  If B = 100 that means base current of around 600 nA.  Through 2.2 Meg should drop a couple of volts which puts the emitter at 3 mA way too much.
TheUnnamedNewbie:
Just running some quick numbers:

You mention that you have about 58mV drop over the 2.2 Mohm bias resistor. That translates to a base current in the order of 26 nA. Assuming a ballpark gain of 100, that gives a collector current of about 2.6 uA.

If we then figure that 2.6 uA has to flow through that 68kOhm collector resistor, we find that you have a voltage frop of just 176 mV drop, so your collector is at a ballpark of 8.8 V wrt ground. Emitter degeneration resistor drops about 1.2 mV. Seems a bit odd to have your output at DC be so close to your rail.

But on second thought, that might be the idea of the circuit. You need your input signal to be so large it pulls down that base till it closes off, and so you get very non-linear behavior. Kinda makes me wonder why they even bothered with that emitter degeneration resistor to be honest.
T3sl4co1l:
Try a voltage divider for base bias.  This may give better results than the "suicide bias" shown.

May also want to use lower resistors, so the output current is a bit higher.  That'll limit performance if the load is heavy.  Likewise using larger capacitors (say 1 or 10 uF electrolytic, positive terminal towards the circuit) will maintain low frequency response when that is the case.

I would suggest:
R2 = 10k
R1 = 220k
Add resistor from base to GND, 33k.

This should amplify cleanly, and shouldn't be disturbed much by reading with a voltmeter.  You shouldn't see much if any distortion, at least until it's really kicking (>3Vpk output voltage swing).  Once it's verified working, you can change the added resistor and see how that affects the sound.

2N4401 is fine, 2N4001 I assume was just a typo.  Mind that if you got them from unverified sellers, you might have, who knows what, floor sweepings, instead of actual transistors in there.  If they're substituted with general purpose Chinese types, it should still work, this is a very noncritical circuit; the problem really is if whether they work at all.

May be worth setting up some basic test circuits to determine what the transistor is, BJT or MOS, N or P, EBC or what.  A voltmeter and resistors should be fine for this.

Tim
MarkF:
As Tim suggested, look at a Common Emitter Amplifier instead:

   https://www.electronics-tutorials.ws/amplifier/amp_2.html

   
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