Need help making a Dunlop Fuzz Face sound good.....

[B Bent]

I have played these in the past and couldn't resist buying a blue FF that came to my attention. I don't think they sound great at all, but I love the case and know that I can pretty easily mod it to a great sounding pedal.(with you guys' help)

have any of you modded a stock FF and if so what did you change? I can get match transistors from Small Bear, but maybe the input cap should be changed as well.

Last question: How hard is it to add a 9V tap. I can drill the hole no problem, but after that is there something special I need to before just plugging in the 9V to the board or will it accept it without many new mods? I suppose I can't just take the leads from the battery and attach it to the tap right?

[joegagan]

some guys might suggest you build a new circuit board for it, but i am of the opinion that the pre-99 dunlop boards are just fine for making a great sounding ff.

note:
if you have a  crest audio/dunlop transition model, i would suggest not modding it due to collectability.  see dave fox's  great story on  crest audio ( owner of dallas music industries in 80s) and the legal deal that went down when both dunlop and crest showed up to a trade show with their own version of the FF!  i think that some or all of the blue ones were part of the crest audio cases that dunlop bought out, not sure which circ baord you have. the crest audio boards were sort of a clearish/ milky white high quality pcb, the dunlop ones were green.

the ge trannies that dunlop used were sporadic quality, some actually sound pretty good but here is my recipe :

put a 2n3906 si in the Q1 position

put a known good  high gain ge trans in Q2. small bear has tested ge trans, steve lists a high gain set for easyface last i checked.

replace the 1k pot with a 2k ; or just place a 2k resistor to ground and skip the fuzz pot, who turns the fuzz down on these anyway?

replace the 8.2k resistor with a 25 k trimpot, then tune collector of Q2 to -4.5v or tune by ear if you like.

presto you are done --sounds good!

yes you can just add the power input to the batt snap but you must use a positive ground power supply, don't try to mix with other power supplies unless specifically capable of independent polarity.

i think general guitar gadgets has a good diagram of adding  a dc power jack, just remember it is pos. ground.

[foxfire]

to help you better...
1.what do you not like about the stock pedal?  
2.what do you want it to sound like?

[B Bent]

to help you better...
1.what do you not like about the stock pedal?  
2.what do you want it to sound like?

I just think that overall the pedal sounds weak. There is not as much girth or balls to the fuzz. It sound thin and fizzy to my ear compared to a good FF clone.

I'd really like to just work with the PCB that is in it, but if necessary I'll drop a new board in and keep my old one around.

I guess to answer number 2. I'd just like it to sound bolder or not so small and fizzy sounding.

[axg20202]

First thing I would do is list the values of all the components in your pedal and compare them to a standard FF circuit schematic. If the component values you have make sense, work from there. Perhaps it is not biased properly? Does you pedal contain Silicon or Germanium transistors and what are their markings?

Google for RGs article called "The technology of the Fuzz Face" - essential reading.

[Gus]

Joe
You can add a 1K "under" the gain pot, disconnect the lug that goes to ground and install a 1K one end to ground and the other to the pot lug.  Now the cool thing is the added resistor is always bypassed by the cap connected to the wiper.  You change the DC bias but the AC gain control stays the same.  Look at the old Vox with the added 820ohm.  In some of my schematics I have a 5Kpot but this is an external to change the sound of the fuzz gated to smooth.

As Joe noted, If it is a Blue Si Crest I would leave it stock and look for another case to build a new circuit in.

[joegagan]

yeah gus, i like that idea!

[B Bent]

UPDATE:

1. I am not sure this is a Crest Audio version, but sort of doubt it since it clearly says "Dunlop Manufacturing" on the back.

2. I ordered some Germanium transistors from Small Bear today.
3. I drew up a little diagram that was meant to help me buy new, higher quality parts. My logic was that maybe with better resistors and such the pedal would start sounding better with the new transistors. Now I am doubting that logic now after reading about the unpredictable nature of Germanium.

4. When you order a transistor set from SB I seem to recall you get a list of values that work well with a specific set of transistors. Could someone elaborate on that for me please?

PS.... I have continued to try and like this pedal stock, but can't quite get there. Even with the volume and fuzz turned all the way up it still lacks overall fuxx and even volume strangely.

[Exactopposite]

what transistors does it have in it?

[joegagan]

b bent,  i was trying to help you. if you had researched the article  i was referring to , you would have seen that it was entirely possible to have a crest audio circuit board while containing some dunlop parts/ this would theoretically make it quite rare.

i gave you other clues as well, but you seem determined to draw your own conclusions. sorry i couldn't map it out 100% for ya.


do whatever you like.

[joegagan]

ok, if it is a dunlop board, the only thing it needs to sound like a really great ff is good transistor and good bias. in my exp all the other parts are fine.

i have never used small bear trannies so i can't comment on using his resistor method, but i know a lot of people here have done it with success. but the trimpot to Q2 collector / Si Q1 solves all probs as far as i can tell and gives you flexibility for the future.

[Gus]

If a Si model.  Simple easy to remove mod could be a 820, 1K, 1.2K " under" the gain pot( unsolder the wire at lug that goes to ground and install a resistor in series)

Look for the Texas Square face schematic on the web.

A fixed at R4
http://www.diystompboxes.com/pedals/gusJH2mod.gif

[B Bent]

b bent,  i was trying to help you. if you had researched the article  i was referring to , you would have seen that it was entirely possible to have a crest audio circuit board while containing some dunlop parts/ this would theoretically make it quite rare.

i gave you other clues as well, but you seem determined to draw your own conclusions. sorry i couldn't map it out 100% for ya.


do whatever you like.

I actually did look at the article as well as research the Crest Audio origins. I assume since the big sticker on the back says Jim Dunlop with an address as well as the same PCB numbering as the Dunlop ones I am good to go there. Also I plan on trying your suggestions as well. I did want to do other things as well, but after researching decided it would be a waste of time and money. That was after I posted last. I am using this guy as a test bed of sorts. I don't think it sounds good right now, but I am sure after all the input I get here I'll have many things to try. I started getting a headache last week I researched so much.

The only thing I had a question about was adding the trim pot. Dont most trimmers have 3 lugs for connecting? If so how do I add it to the two holes that are on the board currently?

[joegagan]

ok cool, i understand a little better.

what i used to do on those dunlop boards to put a 25k trim where the 8.2k resides - solder some little perpendicular extensions to the trimpot that line up with the  resistor holes. solder the right and middle leg of the trimpot together. use leads that are large diameter to support the trimpot floating like that.