Fuzz, So easy ?

[Jyka]

Hi all

I just recently pick up 2 Nkt 275, wich the hfe is 80 for Q1 and 125 for Q2.

Everybody on the web say its easy to build fuzz, but add bias trimmer is not so easy i trought ...

I see the madbean mangler, but when i go on the fuzz face calculator of DIY strompboxes, the bias trimmer is 5k ...

So anybody can help to build good fuzz ?

[jkokura]

With those two transistors, the Mangler is the perfect project for you.

For biasing, use the 20K. It'll give you a broader range of potential bias points. Of course, it might be harder to tune...

Jacob

[Jyka]

Ok thx

I build the mangler with another ge

but, i think the hfe is very important no ?

It's can change the value of the resistor ?

[midwayfair]

but, i think the hfe is very important no ?

Not really. What is more important is that Q1 is lower gain than Q2, ideally with a particular ratio. I've built an extremely good fuzz face with hfe 40 and hfe 60, for instance, though I made a couple other adjustments e.g. the size of the 470R (which helps set the total volume and midrange). Go too high with silicon transistors and you get you oscillation but the Hipster has ways to correct that. As a side benefit, low-gain transistors tend to be less leaky (because the good ones haven't been used up) and they're cheap to boot.

The transistors you posted about are pretty much ideal Fuzz Face gain ranges. The trim pot adjusts the bias so that you don't have to get a weird value for a fixed resistor in place of the 8.2K that's part of the original schematic.

If you haven't read it already, I highly recommend reading RG Keen's "Technology of the Fuzz Face." It's the standard text for the fuzz face.

There are some other fuzzes that you could build with those transistors if you got your hands on a third. For instance a third low-gain transistor would work great with them for a set for a Tone Bender or Buzzaround. Don't focus on the part number, though, because it's going to be really tough getting a third 275. Focus on the gain and leakage characteristics.

And needless to say, DON'T solder those things. Use sockets. It's very easy to destroy them with heat, and who knows you might get some other transistors that you want to try out.

[Jyka]

i read the ff technolgy, but french is my mother tongue and i not sure to i understand everything

[jkokura]

Google chrome will translate the document for you if you want to read it in French. It's not perfect, but it works.

Jacob

[Jyka]

I just finish the RG Keen article ! Great job he made !
But i don't see something about the the player who using single coil or humbucker, i see on diy stompboxes to it's better pot to  250 k for sc and 500k for h right ?

[Jyka]

Hello again,

Want to know something about the power supply of the PNP Fuzz Face, can i put inside a road rage inside my fuzz to plug in to my voodoo lab ? is that changes something on my sound ?

So if i understand the method :

Test the HFE of my transistor : here's it's two ac128 ( Q1 : 82 Q2 : 130) and go on http://www.diystompboxes.com/analogalchemy/emh/emh.html

[PimpMyTone]

Oui tu peux utiliser ton voodoo lab si tu integre un road rage au cicuit .J ai fait ca avec mon tone bender et ca ne change pas le son .

Par curiosité tu es en France ou au Québec ?

[Liustucru]

Oui tu peux utiliser ton voodoo lab si tu integre un road rage au cicuit .J ai fait ca avec mon tone bender et ca ne change pas le son .

Par curiosité tu es en France ou au Québec ?

Théoriquement, tu peux même brancher un effet en positive ground directement dans le Voodoo Lab PP2+ ou ISO5... en utilisant le cable rouge qui inverse la polarité vu que chaque sortie de l'alim est isolée des autres.

Personnellement, je préfère intégrer un Roadrage comme te l'a suggéré PimpMyTone et alimenter le circuit en -9V pour être tranquille quel que soit le power supply que tu utilises. Aucune incidence sur le son.
En plus, une fois construite, tu peux oublier quelle est en positive ground et même la chainer avec d'autres pédales si tu le souhaites.
J'ai aussi construit une SoulBender (positive ground) et une Ti??y (negative ground) dans le même boitier sans problème grâce au Roadrage pour la Soulbender (http://www.madbeanpedals.com/forum/index.php?topic=5827.0).

[Jyka]

francais

[DutchMF]

Damn, Cela me ramène au lycée!!! (Ok, I admit I did a Google Translate on that, but I got the most of what you where doin' en Francais!)

Paul