Zvex - Fuzz Factory

Spazzmatazz · Post by **Spazzmatazz** » 01 Apr 2009, 22:27

the stab problem has some issues, look in this thread.

L_Z_Nut · Post by **L_Z_Nut** » 02 Apr 2009, 03:34

Stab is wired wrong. Rewire it so you jumper drive 1 to stab 3 instead of stab 2.

Fuzzed · Post by **Fuzzed** » 02 Apr 2009, 18:47

Question: Do you think there's much diference between a .1uf ceramic and a .1uf poly?
In tonal qualities of course

P.S: First post

Scruffie · Post by **Scruffie** » 02 Apr 2009, 19:09

I think i'm right in saying that some people find poly to sound clearer, although i personally can't hear a difference thats worth worrying about heres a link to an article if you wanna read up on it but i wouldn't really worry about it ( waits for someone to insist i'm wrong ) http://www.regiscoyne.com/tech/caps&resistors/

Thanks,
Scruffie.

Oh and congrats on the 1st post, welcome to the community.

Fuzzed · Post by **Fuzzed** » 02 Apr 2009, 22:10

Many thanks! That article is awesome!

Unfortunately my fuzz factory doesn't want to sound cool.
I tried a lot of different things, So i came up with this combination of trans:
2n3906, 2n3906, 2n3904.
Believe me, I tried ac188, nkt275, and it sounded way to crispy and the gate knob wouldn't give me an octave at all, or it would give me a crushing sustain octave for half a second

I'm using 4,7k pots for gate, comp and stab, is this relevant?
I'm using a polysomething .1uf capacitor, and the resistors are the same as posted on the french schematic.

The comp knob its totally useless, in tonal quality, when on the max it gives me a synth kinda sound that really pisses me off, so much for the tone of the zachs simulation of fuzz face or anything else.

Sad face.

Scruffie · Post by **Scruffie** » 02 Apr 2009, 23:45

Right first off, awesome your posting comments like this, i think they help everyone, second 2N3906 although PNP, im not sure but could be to low gain ( BC558B are good alternative silicon transistors as i have posted before and a good base) ( i've built 2 fuzzes with them working without issue, dont wanna sound like a broken record )

A big issue might be the fact that the volume & Stab controls should be 5K ( although 4.7k should be ok ) & that comp, gate and drive are all 10k

Finally, what layout have you used and pictures are always useful.

Many thanks ( I'l reply as fast as i can )
Scruffie

Fuzzed · Post by **Fuzzed** » 03 Apr 2009, 00:10

Scruffie wrote:Right first off, awesome your posting comments like this, i think they help everyone, second 2N3906 although PNP, im not sure but could be to low gain ( BC558B are good alternative silicon transistors as i have posted before and a good base) ( i've built 2 fuzzes with them working without issue, dont wanna sound like a broken record )

A big issue might be the fact that the volume & Stab controls should be 5K ( although 4.7k should be ok ) & that comp, gate and drive are all 10k

Finally, what layout have you used and pictures are always useful.

Many thanks ( I'l reply as fast as i can )
Scruffie

Soz my mistake

Volume and stab are 4,7 K
And the rest is 10K

The drive also leads to self oscillation when on tops.
http://membres.lycos.fr/davpseudo/ffactorx.htm

I believe my pots suck big time, i'm gonna buy some alphas with 5k for volume and stab, and 10k to the rest.
I will get some pictures tomorrow.

I didn't get the low gain part, you think that I should use higher hfe's or lower in this pedal?
I tried some npn's still the don't work as suspected.
Well, its kinda akward, since i get lower sustain time with this pedal than with my also diy mxr blue box where the octave and the clean fuzz is extremely wild and long.

Scruffie · Post by **Scruffie** » 03 Apr 2009, 00:26

Right, you want two 5k (4.7k will do) Linear pots and 3 10k linear pots and my gain thing is the 2 main (PNP) transistors you want around the 80 - 120 hfe mark if there old germaniums if silicon you should be ok with 60-200 in general although not great i'm a tad to inebriated at the moment but i will do my best to answer tommorow. but id like to see pics of your builds to check.

Thanks,
Scruffie.

Bernardduur · Post by **Bernardduur** » 03 Apr 2009, 08:35

SPeter wrote:Did you check up the tone stack alone? May be some parts in it are not working! For example I do always check every resistor and cap before placing it on the PCB!Yes, It takes a bit of time but much more less than to debug the whole circuit when it is assembled! Then if something does not work properly I check up the connections!

I now placed the tone stack on the end and that functions great; dunno why but I kept thinking I added it in the middle. Saw my old friend again, opened his up and the same model was in there; sometimes I'm chaotic.

I can really recommend this mod; it makes the pedal more versatile, open and tweakable. It has the bass I need and more mids then anyone would want!

SPeter · Post by **SPeter** » 03 Apr 2009, 17:12

Bernardduur wrote:
SPeter wrote:Did you check up the tone stack alone? May be some parts in it are not working! For example I do always check every resistor and cap before placing it on the PCB!Yes, It takes a bit of time but much more less than to debug the whole circuit when it is assembled! Then if something does not work properly I check up the connections!

I now placed the tone stack on the end and that functions great; dunno why but I kept thinking I added it in the middle. Saw my old friend again, opened his up and the same model was in there; sometimes I'm chaotic.

I can really recommend this mod; it makes the pedal more versatile, open and tweakable. It has the bass I need and more mids then anyone would want!

Hi,
If you have some free time please experiment with gain recovery stage after the tone stack! it may sound even better!Who knows, this pedal may have new dimensions!
Thanks in advance!

Fuzzed · Post by **Fuzzed** » 03 Apr 2009, 20:23

Hey!
While scavenging some parts i found out some germanium trannies.
what do you think about:
2sb187, 2sb270, 2sa201a, 2sa202a, 2sa203b.

Thanks!

Bernardduur · Post by **Bernardduur** » 04 Apr 2009, 16:11

SPeter wrote:
Bernardduur wrote:
SPeter wrote:Did you check up the tone stack alone? May be some parts in it are not working! For example I do always check every resistor and cap before placing it on the PCB!Yes, It takes a bit of time but much more less than to debug the whole circuit when it is assembled! Then if something does not work properly I check up the connections!

I now placed the tone stack on the end and that functions great; dunno why but I kept thinking I added it in the middle. Saw my old friend again, opened his up and the same model was in there; sometimes I'm chaotic.

I can really recommend this mod; it makes the pedal more versatile, open and tweakable. It has the bass I need and more mids then anyone would want!
Hi,
If you have some free time please experiment with gain recovery stage after the tone stack! it may sound even better!Who knows, this pedal may have new dimensions!
Thanks in advance!

I thought about that but the unit already has so much volume that I think I'll keep it like this. It makes the volume knob a lot more usefull!
Btw, I added a second output volume knob (500k, set to max volume) + 500k in series to keep the output impedance correct (as suggested by the Duncan Tone Stack Calculator).

Scruffie · Post by **Scruffie** » 06 Apr 2009, 05:07

For anyone interested i have now written up a build report of the Fuzz Factory on veroboard for Complete begginers, but others may get some use out of it oh and also if anyone builds the factory de fuzz veroboard layout i have made a onboard pot layout, not hard to work out yourself but i've saved you the time and effort.

Thanks,
Scruffie

trad3mark · Post by **trad3mark** » 06 Apr 2009, 10:32

huzzah!!

Most of the parts arrived today. I'm only missing the 5k pots, which i'll get tomorrow and my 3pdt switch, which i've just emailed the ebay guy about. Still though, no reason why i can't solder the parts i have now...

So... will it be easier for a beginner to do it on stripboard or matrixboard?

trad3mark · Post by **trad3mark** » 06 Apr 2009, 11:24

actually, i've already hit a slight problem...

the two jacks i got, one stereo, and one mono, i'm already confused.

the mono has 4 pins (2 on either side) and the stereo has 6 (3 on either side). I know this is a SERIOUSLY noob question, but which pins correspond to which on the circuit diagram?

I promise, no more noob questions after this for a while

Scruffie · Post by **Scruffie** » 06 Apr 2009, 12:56

Yea i was confused by those jacks too, just solder the 2 pins on each side across and the 1 nearest the hole is the ground, centre is the switched sleeve and the furthest one from the insert whole is the tip of the jack, hope that makes sense. 4 pins is mono, 6 is stereo of course.

Thanks,
Scruffie

Scruffie · Post by **Scruffie** » 06 Apr 2009, 17:49

Oh and wether it will be easier to do on strip or matrix is usually up to preference i think, i prefer strip board but maybe youll find matrix easier. That took a while for those parts to arrive from bitsbox, there normally so fast within England, another company i forgot to mention was http://www.bowood-electronics.com although i have no experience with them personally but looks like a decent enough site with a fair collection of components. You may wish to mount those Jacks onto small pieces of veroboard for ease of use, then again you may not!

Thanks,
Scruffie.

trad3mark · Post by **trad3mark** » 06 Apr 2009, 22:27

the bitzbox parts actually arrived on either wednesday or thursday last week, but i only collected them today. I study in a different county to home, about 150km from home like, so i only got round to getting them today.

JUST to make doubly sure about what i'm doing, is all this correct?

the things i'm just verifying are the two jacks, and the pins to use for the pots, particularly stab (maybe just doublecheck the jumpers between stab and drive too??).. Also, i'll need to figure out the pin config for the dc jack, but the data sheet for that is on mouser anyway, so it's not a problem.

Scruffie · Post by **Scruffie** » 06 Apr 2009, 22:31

C3 is orientated wrong, i need to change that on the layout and the pots should all be 3,2,1.
I think other than that, fine.

Thanks,
Scruffie.

trad3mark · Post by **trad3mark** » 06 Apr 2009, 23:07

so they're ALL 321 or is it just stab? so it should (from left to right be) 321 321 321 321 321???

Zvex - Fuzz Factory [traced]