Ever wonder how opamps work? Have you heard the term but are unsure of how to use them? This kit based on the LM1458 Dual OpAmp fills you in on opamp basics and provides a working preamp capable of amplifying miclevel signals to the point where they can drive a power amp. Featuring two highgain stages each with an adjustable output level. The stages can be connected together to provide one highgain preamp or used separately for stereo.