Vintage Components: Germanium Transistors and Guitar Effect Pedals

Hello and thanks for stopping by.

I sometimes come across quantities of transistors and other semiconductor devices made from Germanium (Ge). These are typically old stock since this semiconductor material is no longer widely used and has been replaced by Silicon (Si). It is however, sought after by builders of audio projects - especially distortion effect units for electric guitars. Those in-the-know claim that the unique properties of these Ge semiconductors will create a certain tone that cannot be achieved through the use of Si and certainly not through any use of a DSP (digital signal processor) algorithm.

From an engineering perspective, these unique properties are real and quantifiable when comparing a Ge device to its Si counterpart. Parameters such as bias voltage, leakage, noise factor, temperature stability are a few. However, to a guitarist / distortion effect builder, this quantifiability is described in terms of richness, muddyness, brightness, warmth of the audio output. Component selection is everything and does not stop at with finding the right Ge device. Carbon composition resistors, polystyrene capacitors, and every single part that can effect the final sound quality whether real or imagined is considered.

I do not claim to be a great guitar player, or a designer of audio circuitry. I read the schematics and understand what is going on in the circuit and get inspired by reading technical articles which have led me to build a few distortion (fuzz) boxes over the years. I do know what sounds good and I do know how to find components. One of the more satisfying aspects of what I do is having my sourced parts used by a project builder or boutique pedal designer to advance the enjoyment of their craft. Here is a short list of some of the Ge that has passed through our store...

Sanyo 2SA322 PNP Germanium Transistor

Toshiba M8640E PNP Germanium Transistor