The present invention covers novel approaches to the differential amplification of an input signal. Embodiments of the present invention have precise gain, swing to within micro-volts (μV) of ground, and have high CMRR without the need for precision resistors or tuned potentiometers. Embodiments of the present invention are particularly suited for the amplification of an instrumentation signal for delivery to an analog-to-digital converter. Examples of such signals include the product of a strain-gauge front end, a temperature sensor front end, and certain devices for bioelectronics detection. Embodiments of the present invention which are systems for amplification of a differential input signal can comprise a differential input stage transconducing a differential voltage input signal into a single-ended intermediate current signal using a follower transconductance amplifier, and a single-ended output stage comprising an amplifier producing an output voltage across a resistor network that forms a negative feedback network of the amplifier.