The idea is to develop a more full-fledged Germanium booster in the long run, but we will start with the most basic schematic first. Every update on the project will boil down to a workable booster, a modded clone of it's predecessors.

Introduction: Germanium?

Ever since the boutique pedal craze started to rage, everyone started going bananas on so called NOS germanium transistors because these were used in the very first guitar effects produced -- the original Arbiter Fuzz Face, the Dallas Rangemaster and the illusive Harmonic Percolator all used germanium devices.

The industry has, since the late 60s - early 70s switched over to silicon as the basis of semiconductors, because this proved more reliable. The only freak still interested in germanium are radio amateurs and guitar effect diy-ers. To cut a long story even shorter, there seems to be a general consensus that a well-selected germanium device does have is own particular sonic characteristics. Some has to do with the low gain of germanium in general, and it surely is possible to mimic a low gain device by piggybacking two silicons

Fuzz Face and Rangemaster schematics abound on the net, so the silence on the one stage germanium guitar booster is a bit strange. Back in the boutique, you realize that this is just another attempt to create a marketing hype on something even less complicated than a FF or a normal booster.

Dirty-Boy-Germanium-Boy-Multi-Frequency-Booster-Pedal $350
Electrolead GC £130


So let's get started


A Basic Germanium Booster setup

We will start out with the most basic setup that works (ie. boosts or overdrives) the input signal. My schematic drawing skills are not everything, so note the the output only connected to the collector of the transistor.



Now let's fill out the blanks:

Q1 is a low leakage Germanium NPN, I used 2SD352H with gain of hFE 115.

C1 is the input capacitor -- .022uF or 22nF would be a good starting point, but you can try values up to .1uF
C2 is the output cap - .047uF or 47n for starters, but try up to .1uF (100nF)
C3 is 47uF or higher for more extreme though less defined maximum gain. Connect the negative side to the ground.

R1 is the bias resistor, a 100k trimpot that regulated the voltage fed into the transistors collector. Use the variable resistor to put about 4.5V on the collector
R2 is the gain control, a 5k B potentiometer in series with C3 a electrolyte cap 47uF to ground.

To sum it up, put your guitar signal into the base through an input cap, connect collector through a biasing resistor to your 9V, connect the emitter to ground through an electrolyte and take the output signal from the collector after an output cap.

Your own Germanium Stash

The sonic quality of the result will be largely influenced by the quality of the transistor. You could of course also try PNP Germaniums, which are more common, just remember to switch +9v with ground and turn the electrolyte around. If don't want to go sifting through ebay and buy funky lots that were sifted through too many times, buy them at Smallbear or Aron's stompbox forum for the US and Banzaieffects in Europe (Germany)

I would advice to get a Rangemaster type Ge NPN transistor. hFE's of about 100 will be great, but you can experiment. Considering the single stage design, you might want to try out higher gain Ge's if you have them.

"For linear amplifying, the collector must be more positive than the base; the base must be more positive than the emitter by about 0.4 to 0.7V for silicon, and 0.0 to 0.3 for germanium; the emitter should be the most negative pin. The voltage difference between the collector and emitter is the biggest voltage that the transistor can swing linearly. If the collector is not a volt or more above the emitter, or the base is not a base emitter drop above the emitter as noted above, the transistor cannot be acting as an amplifier." R.G. Keen at Geofex.com

For the 2SD352H I used, I measured the following voltages using 8.9V as source

E = 0.3V
B = 0.3V
C = 4.6V


Well how does it sound? Well a very solid booster with a lot of drive that can overdrive at max gain settings. I do seems to recognize some of that fuzzy, rambling Germanium grit in the sound, If with this minimal parts count, you cannot hear the germanium at work, then when are you going to hear it.

Remember it's only a single stage booster with a gain control as yet. There is more to come, so if you're really interested, subscribe to the modman updates.

Next time we will start finetuning the booster and maybe indulge in some tone control experiments. I'm still developing this as we go along, who know where it'll end? Stay tuned!