Sziklai Step Daughter

This is essentially the same circuit, more or less, as the Darlington Daughterboard I previously posted. The only difference here is that the polarity of  the two transistors must be opposite of each other. The same math applies. Gain of Q1 times that of Q2, and leakage is also multiplied. The cool thing about the sziklai/darlington method is its also a cool way of sneaking germanium transistor into otherwise silicon builds.

Darlington Daughter

A 'darlington pair' is a way of using two low gain transistors together in a way that increases their gain to a useable territory for guitar effect circuits. The polarity of the transistor must be the same in this method. The gain of Q1 is essentially multiplied by the gain of Q2. Example: Two low gain transistors with a hfe of 7 and 10 respectively, but tied together in a darlington pair you now have a single transistor with an hfe of roughly 70. It should be noted that the leakage of the transistors will also be multiplied by each other.

 

Banana Splitter

This circuit has been made and used by everyone and their uncle by now but it's pretty damn good at what it does. This is a signal splitter and buffer of sorts. Does exactly what you think it does, creates two of the same signal. Good for creating stereo effects, or for some of the lighting/indicator circuits I use. Jack Orman/AMZ/Musique seems to be the originator of the circuit or at least brought it to the masses. 

12v Tripler

This circuit takes 12v+ on the input and gives you almost 36v+ at the output. Some of the tube circuits I've been playing with require running the heater at higher voltages so having this laying around has been pretty handy for experimenting with "headrooms". 

How Much?

This circuit will behave as a VU meter. Capable of powering 5 individual LEDs or 10 LEDs arranged in serial pairs. The louder the signal that gets passed through the circuit directly corresponds to how many LEDs will illuminate and for how long. This is one of the first circuits I ever made myself, and remains dear to my heart. It's essentially the schematic given in the data sheet for the IC, but with a few altered values to work with guitar/bass.

Traffic Signal Simulator

Circuit runs three LEDs in a common traffic light pattern. Green(go) light will illuminate for a period of time, then a brief illumination of the yellow(caution) light, followed by the red(stop) light with an almost equal rate of illumination as the green.