# Germanium Resistors



## Rugburn (Jan 14, 2009)

I'm not really a fuzz guy, but I consistantly find the models I listen to or monkey around with that have these germanium resitors, more tonally pleasing than others. I used to have an Ibanez Fuzz Wah. I never thought it was a very good sounding effect. It kinda made my amp sound blown. Any opinions on the "best" fuzz? For me this effect is like Champagne, something I could see myself enjoying once or twice a year. Maybe a BYO project.


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## Solid_Gold_Soundlabs (Sep 20, 2006)

thats germanium transistors, not resistors.

there are lots of different fuzz pedals available, what tone are you after?

Cheers, 
Greg


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## mhammer (Nov 30, 2007)

There are also germanium diodes, used for producing distortion.

"Best" fuzz? Doesn't exist, really. It's a bit like asking what the "best" EQ setting is. You'd be surprised how many seemingly plain pedals can produce some very pleasing sounds when pushed just the right way or listened to via just the right setup. I must have about 40 different fuzzes and distortions, and they all sound wonderful at one time or another. Sometimes they all sound like one another, and sometimes they all sound different from each other.

So Greg's question is the right one: What tone are you after?


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## Rugburn (Jan 14, 2009)

mhammer said:


> There are also germanium diodes, used for producing distortion.
> 
> "Best" fuzz? Doesn't exist, really. It's a bit like asking what the "best" EQ setting is. You'd be surprised how many seemingly plain pedals can produce some very pleasing sounds when pushed just the right way or listened to via just the right setup. I must have about 40 different fuzzes and distortions, and they all sound wonderful at one time or another. Sometimes they all sound like one another, and sometimes they all sound different from each other.
> 
> So Greg's question is the right one: What tone are you after?


Yeah, that's why I put best in quotations. I realized poking around on the net afterward, that it was a transistor, not resistor. I don't really know about this "Germanium" stuff. It came up the other day, when talking to a buddy about fuzzes. He loves them and has a few of them. The ones that he described as having germanium *transistors* seemed sweeter to me. Are these transistors special? Most fuzzes I've tried sound raspy, hard to manage and a little squealy in the higher notes. I guess what I liked most about them was the violin-like sustain. As far as dirt goes it's not really my thing. Maybe I should just take this Germanium stuff as a health supplement, and let it work it's way into my tone that way.

http://www.germanium.net/intro02.php

Shawn


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## keeperofthegood (Apr 30, 2008)

XD

The difference is about 0.5 volts.

What you are looking at when you look at diodes and transistors are bi-metal devices. Two metals. What makes these metal combinations special is that they only let you move energy through them in one direction (generally speaking).

But you still have chemistry happening. It may all be solid, but it is still chemicals. Changing the state a chemical is in always involves some form of energy change. Like freezing water for ice takes energy out, or lighting a match moved a lot of energy out. 

Moving the electrical energy through a diode or a transistor also takes energy. It gets that energy from the electrical energy being moved. In other words it doesn't work by being heated up, or chilled or such, it uses the electricity fed through it to work.

For silicon diodes and transistors, that energy is about 0.8 volts.

For germanium diodes and transistors that energy is about 0.3 volts.

There is a LOT more to it that this of course, but this is the 10 cent intro you would get in high school electronics class when they introduce diodes and transistors.

The difference is about 0.5 volts, and to some peoples ears and in some playing situations or using 'hot' vs 'not' pickups etc that difference can be a lot.


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## Fader (Mar 10, 2009)

Early solid state devices used germanium to dope the junctions but they were prone to premature failure. Silicon produced a more reliable product, so the manufacturers switched.

As Keeper explained, because of their different characteristics of conductivity, they turn on at different voltage thresholds. So they sound different. 

And that's why we get to pay $700 for an original TS-9 on E-Bay.


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## doftya (Nov 1, 2009)

I used to have a Fuzz Face Clone I made from plans I found online somewhere (can't remember where) and I really liked it. I took some advice from somewhere and added a bias pot, which really changed the sound. I could go from a tight and slightly sharp distortion to a nice loose "farty" sound (great when you plugged in a bass). Sometimes I miss that pedal. BTW, Jimi used a Fuzz Face a lot, if that helps.


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## keeperofthegood (Apr 30, 2008)

Fader said:


> Early solid state devices used germanium to dope the junctions but they were prone to premature failure. Silicon produced a more reliable product, so the manufacturers switched.
> 
> As Keeper explained, because of their different characteristics of conductivity, they turn on at different voltage thresholds. So they sound different.
> 
> And that's why we get to pay $700 for an original TS-9 on E-Bay.





doftya said:


> I used to have a Fuzz Face Clone I made from plans I found online somewhere (can't remember where) and I really liked it. I took some advice from somewhere and added a bias pot, which really changed the sound. I could go from a tight and slightly sharp distortion to a nice loose "farty" sound (great when you plugged in a bass). Sometimes I miss that pedal. BTW, Jimi used a Fuzz Face a lot, if that helps.


Yes, silicon is miles ahead of germanium in terms of quality. Where germanium is never bang on, often hit or miss, silicon is regular and predictable. Also, germanium is more sensitive to things, heat and vibration and static, and can be easily damaged or its operating characteristics can simply go "off".

Which is also why those old germanium pedals are worth it too, even Jimmie's. There is a lot written on this, but germanium transistors were inconsistent to the point only a few pedals would sound good, fewer sounded great. What has made it through time are those that sounded better than good to great. You pay for all the chaff that has been lost and tossed to time.


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## Stickman (Oct 27, 2009)

Lots of people use the term "fuzz" for things that are definitely not fuzz. Big Muffs for instance.

To me a fuzz is a Fuzz Face. It's a dead simple circuit with two transistors, three or four resistors and a couple of capacitors. Put simply, it produces distortion by cascading gain stages. The first transistor pushes the signal up high enough that the second transistor can't handle it which causes it to clip. It's not really that simple, there are some extra interactions between the two transistors which affect the sound. With a high input signal, a fuzz gives a huge amount of compression as well.

The other thing about a real fuzz circuit is that there is no input buffer. Because of this you have to consider the electronics inside the guitar as part of the circuit. This is one of the reasons that a FF should always go first if you are using multiple stompboxes. Also because of this, rolling back the volume on the guitar will have a massive effect on how the fuzz circuit behaves. The circuit is so simple that the inherent capacitance of the battery will affect the sound. This is why alkaline batteries sound different from regular batteries and wall warts almost always sound like ass with a fuzz. Slightly dead batteries sound better according to some people, too.

By all normal standards, germanium transistors are total crap. They leak current like crazy, quality varies widely, they change characteristics when the temperature changes, they have a lousy slew rate (how fast they respond to changing input signals) and they have stupid low gain. Once silicon transistors were available, production of germanium transistors stopped. 

In a fuzz circuit, the crappy slew rate and low gain are wonderful. It gives a gentle distortion with soft edges to it. Fuzz circuits with silicon transistors almost always sound harsh and buzzy.

In my opinion the best way to use a fuzz is with the amp dialed in to give little bit of crunch and the volume on the guitar dialed back to about 7. The result is amazingly touch responsive and gives a great bluesy sound that breaks up as you dig in a bit.

In my opinion, paying $200 for a modern Fuzz Face clone, even with hand pick NOS germanium transistors, is a total rip off. Even today, the transistors still only cost $15-20 for a pair, and the rest of the component costs are negligible. The circuit was perfected 40 years ago, so there's no innovation involved, and the only trick is that you need to fiddle the resistor values a little bit to match the values of the transistors (which vary widely for transistor to transistor).


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## doftya (Nov 1, 2009)

Stickman said:


> The circuit is so simple that the inherent capacitance of the battery will affect the sound. This is why alkaline batteries sound different from regular batteries and wall warts almost always sound like ass with a fuzz. Slightly dead batteries sound better according to some people, too.


That's the effect the bias pot had, it changed the ref voltage which mimicked a dying battery. Hence it would start to breakup earlier (great for that on the edge of distortion blues kinda sound), but as you pushed the gain, the breakup would start to degrade and you'd get distorted farts, literally like cheeks slapping. With a regular guitar, it wasn't that good, but put a bass guitar through this with those settings, and it was really cool. I added a tone control which was a basic bass cut control, but the bottom end was suitable for playing a bass through it, then at mid settings, it was more suitable for guitar, then at high settings, it was almost like a Rangemaster when the gain was down.

Like I said, there are days when I miss that pedal. But like you said, Stickman, matching the transistors and keeping them working is not that much fun.


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## Stickman (Oct 27, 2009)

Strictly speaking, that's not a bias but it will lower the headroom available to the circuit.

Most FF's have a "drive" or "fuzz" knob, which is closer to a bias. It's on the bottom right of this schematic:










That knob does two things, as far as I can tell. First, it's going to change the bias of the input signal on the first transitor. I'm not sure how much of an effect it will have, though, because 1K isn't very big. Second, it will choke off some of the current through Q2, essentially limiting the gain of that transistor which will result in less fuzz.


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## keeperofthegood (Apr 30, 2008)

Stickman said:


> Strictly speaking, that's not a bias but it will lower the headroom available to the circuit.
> 
> Most FF's have a "drive" or "fuzz" knob, which is closer to a bias. It's on the bottom right of this schematic:
> 
> ...


Actually, I recall reading that this circuit is best done with different Hfe's. 70 and 30 and I don't recall the recommendation to make which one which, I think 70 in, 30 out but its been a few months. Using two with matched gains apparently makes for a poor sounding Fuzz.


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## Stickman (Oct 27, 2009)

keeperofthegood said:


> Actually, I recall reading that this circuit is best done with different Hfe's. 70 and 30 and I don't recall the recommendation to make which one which, I think 70 in, 30 out but its been a few months. Using two with matched gains apparently makes for a poor sounding Fuzz.


Absolutely, "matching" means to match them to compliment each other, not to find identical ones. I haven't farted around with a lot of them myself, but my understanding is that some of them are so sensitive to temperature that simply handling them with your fingers will change how they behave.

If memory serves, the actual values of the 470 and 33K resistors in the circuit will need to be tweaked to match the transistors used. I think 70 & 120 are the accepted "best" hfe's for Q1 and Q2 respectively.


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## 2N1305 (Nov 2, 2009)

Stickman said:


> Lots of people use the term "fuzz" for things that are definitely not fuzz. Big Muffs for instance...
> 
> In my opinion, paying $200 for a modern Fuzz Face clone, even with hand pick NOS germanium transistors, is a total rip off. Even today, the transistors still only cost $15-20 for a pair, and the rest of the component costs are negligible. The circuit was perfected 40 years ago, so there's no innovation involved, and the only trick is that you need to fiddle the resistor values a little bit to match the values of the transistors (which vary widely for transistor to transistor).


I agree with most everything you said. However it did seem a bit contradictory when you said Ge transistors were unreliable and had low gain, were generally "crappy", yet praise the sound of original Fuzz faces and admit the Si circuits are harsh and buzzy.

Frankly, I find their inconsistency and variations give them character. Makes product reliability an issue though...
So what does that tell us? don't convert Ge circuits to Silicon, it'll suck more!

Need Germanium? visit: 2N1305 on Gearlslutz ( www.gearslutz.com )


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## Stickman (Oct 27, 2009)

2N1305 said:


> I agree with most everything you said. However it did seem a bit contradictory when you said Ge transistors were unreliable and had low gain, were generally "crappy", yet praise the sound of original Fuzz faces and admit the Si circuits are harsh and buzzy.


I really tried to choose my words carefully. I said, "By normal standards", meaning if you were going to use them as the designers intended. You know, to build a computer or as a component in a high fidelity amplifier or something like that.

Creating a circuit to deliberately push a component outside its operating parameters and then relying on its undocumented characteristics to produce pleasing distortion isn't what most people would consider a normal application. It's just a happy coincidence that some of the same characteristics that make Ge transistors substandard for many normal applications also make them great for FF circuits. See? Not contradictory at all.


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