First fuzzbox build gone wrong... But how ?

[Keysershades]

Hello! I made this layout from a Fuzz Face schematic on the net http://s796.photobucket.com/albums/yy249/keysershades/?action=view&current=FF-1.jpg and it's all right in my eyes but where did i go wrong ?
I Hope you can understand my drawing!
Please help me. The tranny's are NOS BC109C's
Resistor values:
-33k-
-100k-
-330k-
-1k-
-820-

Shades

[dthurstan]

Hi

It's quite a confusing way to layout the circuit. Have a look at http://www.generalguitargadgets.com/pdf/ggg_ff5_sc_npn.pdf

From what I can see the 2.2uF cap is the wrong way round & the base of Q1 isn't connected to the collector of Q2, for a start. I also think some of your resistor values look wrong. Do you have a pic of the original schematic you based it on?

[Keysershades]

Hey, i build it on this schematic http://www.antilife.org/pedal/03_fuzzface_schematic.gif   .
About the resistor values, i "modified" it to the "Hendrix" mod.
Thats why i raised some of the values, does it make sens ?

Simon

[anchovie]

Who's "Hendrix mods" page told you to change the 8K2 resistor to 330K? I'm pretty sure that's way too high!

[Keysershades]

Okay now i see what you saying! But i think that i made a mistake making the layout (made it doing a launch brake without having the original by my side). So the ORANGE resistor is 18k not 330k.

I doubt very much it's because of the resistors my pedal is not working.

[Keysershades]

Here is a updated layout.

R1= 1k
R2= 33k
R3= 100k
R4= 18k

C1= 2,2uF
C2= 20uF
C3= 0,1uF

[Keysershades]

And here is the link... Sorry.
http://s796.photobucket.com/albums/yy249/keysershades/?action=view&current=FuzzFaceLayoutfrdig.jpg

And by the way, i'm not completly sure how to ground the joint that is connected to emitter of Q1 and fuzz pot. leg 1. Can you tell me that ?

Shades

[slacker]

The connection between the 2 transistors is wrong, if you've built it like that it won't work. The Collector of the first transistor (the bottom of R3) should go to the base of the second one, you've got it connected to the collector.

[Keysershades]

Your right, actually that's just a mistake in my layout. The base of Q2 is connected to R3 abd Q1 emitter.
But i made some changes and now i got a small amount of signal ! it is almost nothing. So if i got almost no sound, what would that be ?

Simon

[Barcode80]

You resistor values, especially in this particular circuit, are CRUCIAL. the assumption that a part value won't affect the outcome is way off base. double check your resistor values, as some of them set the bias for the transistor, affecting whether or not you get any sound...

[tiges_ tendres]

Your right, actually that's just a mistake in my layout. The base of Q2 is connected to R3 abd Q1 emitter.
But i made some changes and now i got a small amount of signal ! it is almost nothing. So if i got almost no sound, what would that be ?

Simon

Have you tried building it with the confirmed values on the fuzz central schematic you have posted?  I think it's safe to say that a lot of us have successfully built this pedal, with that schematic. 

I think it would be a better idea to get the pedal working with a confirmed schematic/values, then start tweaking, not the other way around.

Could you also maybe post voltages of the transistors per the what to do when it doesnt work sticky?

[Keysershades]

YES!!! It's alive and a beast! I build it like the basic fuzz face from fuzzcentral (like you told me to) and now it works!
BUT, it's a bit noisy ? And really hard in it's tone.
Any suggestions how to mellow it out ? Or is this just a case of bad silicon tranny's ?
If so, i guess this is just how germanium fans describes the early silicon FF's! Which is not how i planned this project to be!
Last question, is it possible to make a "bad" Fuzz Face good?

Shades

[tiges_ tendres]

YES!!! It's alive and a beast! I build it like the basic fuzz face from fuzzcentral (like you told me to) and now it works!
BUT, it's a bit noisy ? And really hard in it's tone.
Any suggestions how to mellow it out ? Or is this just a case of bad silicon tranny's ?
If so, i guess this is just how germanium fans describes the early silicon FF's! Which is not how i planned this project to be!
Last question, is it possible to make a "bad" Fuzz Face good?

Shades

Its easy when you follow the proven path for your first builds!

When you say it's noisy, you'll have to give us some more information.  How is it being powered?  Do you have this thing in an enclosure or on a breadboard?

There probably isnt anything wrong with your transistors, although you might want to follow peoples notes here for tuning the fuzz face.  Common results have shown that a lower gain transistor in Q1 one pairs well with a higher gain transistor in Q2.

Testing Silicon transistors for gain is fairly simple if you have a DMM with an HFE function.

[Barcode80]

YES!!! It's alive and a beast! I build it like the basic fuzz face from fuzzcentral (like you told me to) and now it works!
BUT, it's a bit noisy ? And really hard in it's tone.
Any suggestions how to mellow it out ? Or is this just a case of bad silicon tranny's ?
If so, i guess this is just how germanium fans describes the early silicon FF's! Which is not how i planned this project to be!
Last question, is it possible to make a "bad" Fuzz Face good?

Shades

by the way, IME you have this backwards. Germanium transistors, as far as I can tell, tend to offer a smoother tone, Silicon a more harsh tone. Also, tweak your resitor values. Unless you are using one of the schems that was specific to silicon transistors, the resistors from the power supply to the transistors need to be tweaked to accomodate the silicon transistors. IOW, silicon transistors are not always plug and play in place of Germaniums.

[Keysershades]

Yeah i got in a Fuzz Face "landmine" incloser and powered by a 9v battery. It is noisy in the way of a crappy single coil stratocaster, if you know what i mean ? But i think that have something to do with the huge amount of gain from the bc109c's i got in it, so maybe i should get a low gain for Q1!
I build it with the same resistor values from the silicon fuzz face schematic from fuzzcentral.com.
I'm going to place a bias pot, but i only got a 50k ohm and a 100k ohm pot so i gues i have to put it in parallel with a resistor to get it down in a value that makes it more control-able ?
And yeah the resistor values a the same as in a germanium FF so any sugestions on which ones to changes ?
I'm planning on changing all the resistors to carbon comp because it heard that it removes some of the harsh tone, and i just happens to have a bunch of old resistors

Shades

[smallbearelec]

One big suggestion as you learn to Own Your Tone: Learn to use a solderless breadboard! This article:

http://www.smallbearelec.com/HowTos/Breadboarding/Breadboard.htm

takes the Fuzz Face circuit, walks you through setting up the silicon version, BIASING, and some tweaking out of the harshness that's inherent to silicon. I don't discuss using germanium devices, because selecting those is really a separate topic, but the setup method shown is easily adaptable to Ge with very few changes.

The point of doing it this way, clearly, is to not frustrate yourself with hard-soldered builds that don't sound like what you have in mind. NB: composition resistors won't soften the tone. Germanium will, or selective filtering/biasing/choice of gain buckets in the silicon version may give a result  that you like. This kit:

http://www.smallbearelec.com/Detail.bok?no=982

is inexpensive and includes a lot of goodies for experimenting. Congratulations on getting your first build done!

Regards
SD

[Keysershades]

The fuzz is getting better and better for every day now! But it's almost to fuzzy, i read about adding a trimpot to control the input,... anybody tried that  ?

Simon

[tiges_ tendres]

The fuzz is getting better and better for every day now! But it's almost to fuzzy, i read about adding a trimpot to control the input,... anybody tried that  ?

Simon

Yep, Sure have.  Also the volume control on your guitar will do the same thing.  You might be better off not using a trimpot for that though, especially if you are having noise issues.  Often I've found that trim pots on certain parts of the circuit will add more noise. 

You also mentioned using Old Carbon Comp resistors to remove some of the harshness.  You are probably going to find your circuit gets noisier if you do this.