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.