Low Noise Amplifier Circuits

Composite Amplifier Improves Noise : 08/04/94 EDN-Design Ideas 

Low Noise Amplifier for Phase Noise Measurements: features less input noise than a 50 ohm resistor.

Low Noise Balanced Microphone Preamp: very low noise, close to the theoretical minimum, high hum rejection and variable gain with a single rotary pot, similar to that used in many professional grade mixing desks.

Low Noise Microphone Preamplifier

Low Noise Variable Gain Amplifier