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If you changed "both direction" for those tranzistors, they are probably damaged now, because of reveted polarity. By the way, germanium tranzistors have slightly another characteristic with bias voltages at Basis. Generally, at output electrodes (here colector of Q2) you should have cca 1/2 of Ub, so cca 4,5 V. Try to play with R1 and then with R2 to set it. For another tranzistor respect the pins assigment. See schematic I sent below.

Hi, you can use as npn, as pnp tranzistors, which has little different "oldie" sound. Only take care of proper pins connect. For PNP you must only swap polarity of battery and all polarized electrol. kondensers. And little lower noise, connecting some small capacity (cca 330pF) between basis and output electrode, mostly collector. Basic schema is here:

[power]

Here is orig doc I have, in pdf.
For an example I am sending Tube Head schematic too - notice that power branch for triodes. Three systems of 4049 from charge pump are connected as the power generator, able to work with elyts in charge pump. But over this all, there is elyt at the end to stabilize power from HF oscilations. Woe, my english is not too great, but I hope you understood :@)

[But,]

I guess that this it that schematics?  C18 and R2 are not used or assigned in my original document. Try to control it (and play around). C17 seem to me too low - I should use minimally 470pF and the same cap (for proper voltage) I should connect from anoda to grid of first triode. But, the biggest suspect I have to that charge pump, which have only 47n cond at the end where should be power for triodes (cca 60V). I would add there elyt cca 1-10uF/100V. Fuell will rise little slowly there at the start (seems like as the valve heating :-), but it will be more freq. stabilized.

Any schematics for considering? I mean that Tom's variation? Where I can see it?

By a way, at one schematic I found at web, for R11 is value 1k5. But for most others plans there are 15k! It will dramatically change sound! Even some caps have another values, but mostly only slightly in compare with anothers. As you can compare in links I sent before.

Maybe you could play around this enhanced Klon of Klon...

Hi Half Smith, those settings will aproximate proper values of caps. 22n+4n7 will give 26n7 etc... But, for those Low pass filters putting off clock frequencies from signal this will be almost the same put there values, you have. Resonant freq will be moved slightly to the higher F0. Listen signals with high freq (aliquotes on strings) and controll if there are not interferencies (ring modulations). If not, don't mind it. Aditional caps you can connect there allways. Feedback pot is not problem - it is only volume divider.

Those links may help to understand all about this toy.

https://www.electrosmash.com/klon-centaur-analysis
https://www.coda-effects.com/p/klon-centaur-mods-and-tweaks.html
https://rezzonics.blogspot.com/2016/09/klon-centaur-3v3-clone-ltspice-analysis.html

Sorry, mistake...

Hi, those are lowpass filters for certain frequency - to work properly, it is better to use values in schematics. (let's suppose, that they made proper setting calculation) At the other side, this is not so important position, so you can slightly experiment. Paralelly with 22n join 4n7, and paralelly with 3n3 join 560pF. That would be sufficient.

WOW! So now I am Diode Destroyer? Well, my post list is little thin now, but contrarry I am sending long ones! :@)

By the way, somehow under my name Zerro shows Diode Destroyer, which is probably some your "tag". I am new in this web, so I must yet set it away from my account...

Great! So, no big issues were here. And basic max gain is ok? I mean, gain without compression.

Hug, Destitute!
Let's suppose, that yout PCB desk for BearHug V2-1 is connected ok :@)

1 - Control Q1 and D2. If they are still alive. Those details are sensitive for overheating while mounting, especially diode. Let there slightly longer "legs" for it. And that MOS-FET (and J-FET too) are sensitive for static electricity while handling and soldering. Learn about handling with it (if not yet).

2 - If they are good, play around TRIM 100k to get cca 4V at Drain (output signal) electrode of Q1. It's cca a half of fuell after D1. If it is ok, you have set basic DC setting for audiopath. Otherwise Q1 or D2 is "fired".

3 - Now you must set proper gain for it, not to have distorted signal. Disconnect C8 100nF from common point with diodes D3 D4. Now your J-FET Q3 has no signal and it's Gate is grounded by R7-R9. So, it's D-S pass is maximally opened, as can be for this schema. If this Q3 is good (again controll), then Q1 has now max. gain.

4 - Put sinus cca 2V/1kHz to input and measure (best by osciloscope) output. Or simply hear if signal is ok, without distortion, for maximal guitar signal. If there is problem, you must lower gain for this Q1 - serially with C7 47uF connect trimmer cca 10kOhm and try set clear signal, cca 2x stronger than original. If you are succesfull, you have finished basic audiopath setting. If even bigger value of trimmer doesn't give clear signal, try to play again with Q1 bias with 100k TRIM. When it is ok, change that serial trimmer for gain with resistor with closest higher value. If distortion is still here, Q1 or D2 are "fired". Especially, when you can hear noise. Axchange it and try set all again. If still noise or distortion is here, try to connect C7 straight at ground, bypassing Q3. If distortion or noise are away after we play with gain or TRIM trimmer, Q3 is bad - doesn't work as resistor. Exchange it.

5 - Now we must set Q2 - comp driver stage. At Collector of Q2 must be cca half of fuell voltage, which is cca 8V. Play around Basis resistor 10M. By me, is it too big to open it properly! I suggest 3M9, maximally 4M3, to get there cca 4V DC. Set it by trimmer at first and again exchange with similar resistor. Pot COMP 1kOhm set at minimal value while setting, so that resistor R10 47 Ohm is practically at ground. If it's ok, you have now strong enough signal for driving compressor branch. If signal is weak, you can change value of R3 2k2 to 4k7, as described in manual. But for the best range of setting this driver stage, change pot COMP too, at 2k5. And again set those 4V at Collector. If you can't set this voltage 4V DC, Q2 is probably bad.

6 - Now, connect C8 100 nF again with diodes. If you play some signals at the input now, at Gate of Q3 you will measure some negative voltage changes. Use digital meter, with high impedancy here. This minus jump will close D-S pass for Q3 and so lower gain of Q1. If negative jumps are ok, but signal is bad or without change, Q3 is probably bad for this work - try another.

Thats all.