Arbiter Fuzz Face Clone – Assembly Instructions

Welcome to the Genuine Arbiter Fuzz Face Clone Kit Instructions! It’s a great circuit and it’s an easy build, so let’s get started! This kit can be purcahsed with either Germanium AC128 PNP transistors or BC588 Silicon PNP transistors.

BOM Layout


DA Fuzz Face Layout

Assembly Instructions

Attention: Changes may occur after the Assembly Instructions are created and the photos may not reflect those changes. Always use the BOM to verify the placement of components.

PCB Components


Locate the silkscreen component identifiers for R0, R1, R2, R3, R4, and R5.  Insert each resistor into the correct through-holes and solder them to the board.


When placing C1 and C2, use the picture above to help you position these electrolytic capacitors.  Note the black band; this indicates the negative polarity lead of the capacitor.  To further assist you, the PCB has a ‘+’  and a square through-hole for the positive lead and a  circle through-hole for the negative lead.

C3 is a ceramic capacitor and it does not matter which lead goes into which hole.


Make sure your transistors are oriented correctly! Each type faces a different direction!

2N3905 Transistor

2N3905 Transistor Orientation

Germanium AC128 PNP Transistor Orientation

Germanium AC128 PNP Transistor Orientation



Silicon PNP Transistor Orientation

BC558 PNP Transistor Orientation

Pay special attention when placing the transistors onto the PCB.  Each of the three leads has a specific function and the circuit will not work if they are placed incorrectly.

When using the silicon 2N3905 or BC558 transistors, follow the orientation in their respective photos.

Germanium transistors: Line up the little tab on the transistor with the tab on the board as shown in the first picture above. Q1 gets the lower gain transistor (if you are using Synthrotek’s transistors, it will be marked with a black dot). Q2 gets the higher gain transistor.

The trimpot has three leads.  Orient the trimpot as shown in the picture above and insert the leads onto the PCB.  If the leads are bent, gently bend them to conform to the through-hole layout on the PCB.  Once the circuit is completely built, you can adjust this trimpot to color your sound to your needs.

That is all for on board components.

Wired Components



 Wire the pots exactly as shown in the picture above (the top one is the A500k and the bottom is B1k). Make note that the B1k pot is reversed from the orientation that most of our pots use.

We suggest soldering wires to the potentiometers before attaching them to the PCB.  Having to de-solder a too-short wire from the PCB is an extra step that can be avoided.  As always, use more wire than you think you will need; wire can always be cut.

When installing the pot, some pots come with nubs near the shaft that may get in the way of installing the circuit into a case. Check for a nub and clip as necessary.

Cut the pot nubs

Don’t forget to cut the nubs on the potentiometers as neccesary.

Input/Output Jacks and Power Jacks


The ‘In’ Jack of the Arbiter Fuzz Face Clone circuit uses a 1/4″ stereo jack which turns off the power sources when nothing is plugged into it.  When you plug a mono plug into the jack, the circuit receives power.

Stereo jacks have three solder lugs for the 3 different parts of the stereo signal: Tip, Ring, and Sleeve.  On the PCB, they are identified as ‘T’, ‘R’, and ‘S’.  Attach each solder lug on the jack to their respective PCB connection. Make sure to use the solder lugs as pictured above.

On the other side of the board is the ‘Out’ PCB connections.  They are marked ‘T’ and ‘S’ for ‘Tip’ and ‘Sleeve’.  Mono jacks only have these two connections, so they are easy to wire up.

The 9V battery jack is easy to put onto the PCB.  Take the red wire and insert it into the square through-hole with the silkscreened ‘+’.  The black wire goes to the circle through-hole marked with a ‘-‘.

DC Jack Pinout

DC Jack Pinout

The DC Jack has three solder terminals that connect to the PCB.  Use the picture above and the silkscreen on the PCB to place the wires correctly.  The DC Jack allows you to power your circuit with a wall wart and disconnects the 9V battery from the circuit, saving money on expensive batteries.

NOTE: please remember to use a 9 volt center positive power supply. Using the incorrect power supply polarity will damage your circuit.

If you do not want to install the 9V DC jack and only install the 9V battery clip you will have to short the S and C pins for the 9V DC Jack like shown in the picture below*.

* Your PCB may not look exactly like the photo, that is ok. What is important is that you short the same pins as shown in the photo.

No DC Jack

Short these contacts to get the circuit to work without the 9V DC Jack



Insert the LED through the plastic insertion mount (if needed) and solder wired leads to both legs. Connect the wire leading from the flat side of the of LED to the solder pad on the board that is closest to the flat spot on the silkscreen. The picture below shows the flat spot (although the led is board-mounted). You may omit wiring the LED and mount it directly to the PCB. The photos below illustrating stomp switch wiring show the LED installed in this configuration.

Stomp Switch


Stomp Switch Help

 Line up the number code from the switch to the board exactly how it is labeled in the picture (above and below.)

Make sure the flat blue side of the stomp switch is facing up when comparing it to the picture below. Either Blue Side will work fine. AND YOU CAN MOUNT THE STOMP SWITCH DIRECTLY TO THE PCB IF DESIRED.


Stomp Switch Help


Stomp Switch Wiring

Biasing Instructions:

Power on the pedal and insert a cable into the input jack. For the circuit to be optimally biased, the collector of Q2 needs to be at 4.5 volts. (When connecting the Arbiter Fuzz Face Clone circuit to your multimeter as shown in the photos below, your meter will read -4.5V.) The 20K trim pot is used to dial in this value. All you need to do is connect your leads to a ground on the PCB and the collector of Q2 to get this reading.

Synthrotek Arbiter Fuzz Face Clone Biasing GuideArbiter Fuzz Face Clone Biasing Guide

Congratulations, that’s the end of the instructions for the Arbiter Fuzz Face Clone circuit!  If everything is wired/connected properly, you should have a fully functional fuzz pedal.  Remember to adjust the trimpot to get the sound you want from your new pedal and have fun!


  1. todd says:

    hey send me a link to where i can purchase the kit for this

  2. zoran says:

    awesome kit. can you please post the resistor values for r0, r1, r2, r3, r4 and r5, as well as c1 and c2? cheers

  3. zoran says:

    I figure c2 to be 22uf, and c1 to be the 2.2uf cap

  4. Stephen says:

    can the wires on the dc jack be switched in order to make it center negative instead of center positive? if so, i could use it with my pedal power without having to buy a special power cable. thanks!

  5. klk says:

    Unfortunately no. Given the interconnections of the DC, input and output jacks this will cause various different issues depending on the actual source. For example if the source supply is shared with another circuit the act of connecting a reversed Fuzz Face and another pedal would cause a short circuit in the power supply.

  6. Keith says:

    This will not eliminate the issue unless the power supply plugged in the adapter mentioned is a separate for the one supplying power to the rest of your components.

  7. Tom says:

    Is the box not provided? I can’t find any reference to the housing or box enclosure

  8. Keith says:

    Boxes or enclosures are only included with our kits that specifically state “with case” or other similar wording. Many of our customers prefer to place their DIY projects in their own, often unique enclosures. We are in the process of matching each kit to a case and a recommended drill pattern for that case. Once that is completed all our kits will have a “with case” purchase option.

  9. Mike says:

    Is it possible that the R1 shown in your photos is a 33 ohm resistor? I believe it’s supposed to be 33K ohms.

  10. Mike says:

    My mistake. You’re using a 5 band resistor.

  11. Keith says:

    Mike, That’s correct, R1 is a 5 band 1% resistor showing orange orange black red which is 33.0k and the tolerance band is brown indicating the 1%.

  12. Vince White says:

    Is it possible to install a external 10k trim pot and is the pot a A or B taper?

  13. vince says:

    Will a standard 5% resistor work if I find one that is 33.0k give or take 1%? Will a 10k log taper multi turn pot work mounted with a knob instead of the trim pot? Thanks in advance for your reply.

  14. Steve Harmon says:

    Hi Vince, I think that could work, and no it does not have to be a trim pot, that will work fine, thanks!

  15. Steve Harmon says:

    B – log thanks!

  16. Steve Harmon says:

    Yes and B, thanks!

  17. Admbmb says:

    A few questions…I built this and the whole circuit is extremely quiet, even after playing with the trimpot (volume is normal when bypass switch is enacted. My kit came with a red LED instead of the green one pictured. Does it matter which way the LED is positioned? After completing the circuit, the LED would not come on, even after resoldering it both ways. Like I said, my output is extremely weak, even with a brand new battery.

  18. Steve Harmon says:

    Hey Admbmb, there is certainly something wrong, it would not have a weaker output. The Red LED will not affect the circuit, however LED’s are polarized, so it does matter which way they are connected to the circuit. The Shorter lead on the LED is Negative and the Cathode, the Longer is Positive and the Anode. The PCB has a + and – where the LED is positioned. Also the Trim pot will affect some things, but overall it biases the Transistors, if you have turned some and the output is still low, I dont think that is the issue. Can you confirm that you have your Transistors are aligned properly? Also, are there any other components that you may have reverse polarity on? Let me know if I can help further. We can offer repair services if need be.

  19. Mike says:

    I have the same situation as Admbmb. Normal bypass, weak output with 3DPT switched on, no LED power. Is the DC jack essential to the circuit? I haven’t installed it. Is there a schematic I can use for troubleshooting?

  20. Steve Harmon says:

    Hi guys, YES the DC jack is essential, it is part of the circuit and has to be installed, please let me know if this fixes it.

  21. Mike says:

    Thank you. I should have seen that. For those wanting to go battery only, and not include a provision for using a DC jack, it’s necessary to connect/solder a jumper from S to C in the area of the PCB where it says DC Jack. I just tested this and now I get the LED and Fuzz, just running off a 9V battery.

  22. Steve Harmon says:

    Thanks Mike, this will help a bunch for folks. We mention this on a couple other kits, but not this one… 🙂

  23. Admbmb says:


    So…I had no markings on the PCB indicating which side of the LED mount is + or -. Is the flat side of the LED supposed to correspond with the flat side picture printed on the PCB? I’ve had no luck with the LED lighting and have installed it both ways. I was able to get a fuzzy tone, but by weirdly lowering the level pot instead of raising it (and with the LED mounted with the flat side opposite of the picture on the board). I’ve checked, double-checked, and then whatever 20X checked the instructions and can’t figure what the deal is. I also installed the DC portion of the circuit and have tried it with a battery and with the adapter. Let me say that I love the price on this kit…love your site…and would love to see you have more kits (in which I would buy). Love to see an Octavia, Tonebender and Rangemaster kit.

  24. Steve says:

    Hi Admbmb, the Flat side does correspond to the Flat picture on the PCB. If you switch the two outermost leads on the pot the pot will function as you like, that is just a wiring issue. The LED should be mounted on TOP, but if you get the polarity correct, it really wont matter, and should work either way. So the pedal “works” just no light out of the LED? Perhaps there is something wrong with the led…? Thank you for the suggestions, we will certainly have more kits soon, thank you!


  25. tom says:

    Did the 10K B-log taper pot end up doing the job? I just saw your post and it looks like a good idea. I haven’t started the build yet and am just working out my controls.

  26. Syphonear says:

    I just assembled this board and it sounds just like I imagined it would. The Fuzz and Level both work to produce a wide range of fuzz tones with that unmistakeable Germanium seasoning. On my working board, the Fuzz pot works backwards, so as I turn it clockwise, it lowers the output. As Admbmb has noted, my LED does not work. I wired it as per the diagrams and put the positive lead into the square + hole on the board. I believe I probably need to check the wires to the DC adapter and swap C and S. Will report back if that works. Again, this is a great kit and provides the tone as expected, even for a novice electro-head like me it was a simple build!

  27. Steve Harmon says:

    Hi Syphonear, really glad the pedal sounds to your liking! You can swap the two outermost pins on your pot to reverse the backwards issue. Yes please check your wiring, or shorting of the DC jack, it is essential to the circuit. Thanks again!

  28. Syphonear says:

    Thanks Steve, I am aware of the need for the LED in the circuit…but honestly, it sound great without it right now. I will swap the pot wires and that should do it. Just a side note, I played in the 1960’s and used the old Maestro Fuzz Tone by gibson. In resurrecting the sound of that era, this is a faithful replica of that “sacrosanct” tone.

  29. Steve Harmon says:

    Yeah, no worries about the LED, it should not affect the sound. I meant that the DC jack has to be installed or the PCB shorted for the LED and pedal to work as described. If it works, rock it! Thanks again for the kind words!

  30. Admbmb says:

    Yeah…thanks for all the help. Fuzz works great. I’m sure it has to do with the choice of transistors and how I have it honed in on the bias with the trim pot, but this completely slays the real germanium fuzzface that I own. Its just a brutal blissfull bloom of fuzz that cleans up nicely with the volume knob. Great work…had a blast. Will def be building another one.

  31. Kenneth B says:

    Is the resistor for the led soldered to the board? Or is it soldered to the led?

  32. Steve Harmon says:


    All soft components such as resistors and capacitors are soldered to the board.

  33. Kenneth B says:

    Which resistor is for the led?

  34. Kenneth B says:


  35. Steve Harmon says:

    @Kenneth B

    Yes, connections around the LED is that the pin on the flat side of the LED goes to the center pin of the 3pdt stomp switch and the other end goes to the resistor R4, and resistor R4 goes to ground.

  36. Kenneth B says:

    I wired up everything per your instructions. I powered it via the DC jack. When I turned it on the led came on, but there was no signal. Then the 500k pot started smoking, so I turned it off. Also the battery clip didn’t work.

  37. Steve Harmon says:

    Hi Kenneth, did you use a 9V center POSITIVE ac adapter? May be the issue. Can you send me any more info? Super sorry!

  38. Kenneth B says:

    I removed the dc jack and I shorted the s and c pins. The fuzz works now, but only if the 500k pot is removed. I tried using a different 500k pot, and I got the same results. It seems like it’s grounding out when I connect the 500k pot. I checked all of my solder joints and none of them are touching.

  39. Steve Harmon says:

    Hi Kenneth get me an email if you like and I can figure out this specific issue. It sounds like the DC jack was wired incorrectly. I have never had a pot smoke (ha ha), so something most likely got damaged. We will figure it out.

  40. Kenneth B says:

    My email is I can send you some pictures of the circuit if that helps.

  41. Ralf says:

    Hey guys,

    just as a cool tip, you could put a simple SPST switch betwween S&C connections from the DC jack for adding a convinient ON-OFF funtion.


  42. cristian says:

    hey there,

    I used the fuzz face PCB with very good results. But, i want the led very low energy consumer, so i add a 47 k resistant to it before i put it in the PCB.

    So….I wonder if one of the resistant in the PCB its dedicated to regulate the led diode. may be r4???…the idea its to change the value of this resistant to 47k and avoidme the job to add a resistant to the led….

    please let me know, i really apreciate your help..

  43. Steve Harmon says:

    Hi Cristian,

    For the Fuzz Face, R4 is the resistor for the LED.

  44. Steve Harmon says:

    That would certainly work, though the when you don’t have anything plugged into the Input and the stomp-switch in Bypass mode the pedal doesn’t consume any power.

  45. Cristian says:

    Dear Steve

    Me again, i had a little problem… as you know, the synthrotek germanium daa fuzz are negative ground. For this one in particular i just using it with baterry power source. It function flawless and no problem at all individually.

    BUT when a conect the fuzz to a fully functional synthrotek RAT clone, positive mass, powered with a separate power souce it comes a problem;

    when I put the RAT first and the daa fuzz second in the line to the amp (The fuzz conected after the RAT), sounds flawless, bypass and both effects operating together with no problems at all.

    THE problem, the strange problem, its when i put the germanium fuzz first before the RAT… in this case the stuff does not sound at all, totally death. But more important too…they dont soun even when i put both of it in true bypass mode…very very strange….or may be..very misterious…:O)

    Unfortunately fuzz first and RAT after it is the configuration I would like to have, in order to modulate the fuzz treble with the rat and get a more modulated fuzz sound.

    So, may do you figure out why this happens….and how to fix it?

    I have the impression that the matter relates to the different polarities, that sound logic… but why work in a way, and do not in the other way? … this time, really a big mistery for me….

    Some tips……y used an aislated plastic jacks for input and ouput in the rat…and do not remember that they was conected to the chasiss… deed, y dont remember that any part was conected to the chasiss…..may be the power jack???…..But its naturally do not generate hum or excesive noise…so i dont bother for that…

    But, for the fuzz, in deed after first test, it have a loud hum that disappearalmost complete when y conect the sleeve of one of the plastic aislated jack directly to the chasiss using a soldered cable……Any way, when i used a switchcraft cain of jack…it automaticly conect to the chasiss because have a metal contact with it and no sound at all…but here born a secondary cuestion…when we use plastic aislated jacks in your effects, its a must to conect the sleeve of this jacks jacks to the chasiss??

    well..thansk for your time, and y Really appreciate your help. Please let me know at my mail because the sistem so not warn me when i get an answer.


  46. Cristian says:


    huuu…a mistake….the fuzz have the positive ground, and the rat have the negative ground…the problem its steel the same.

  47. Steve Harmon says:

    Hi Cristian, are you powering them from the same Power Brick/Wall Wart? The Fuzz Face would need its own 9V center Positive power supply.

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