--.--.--.--.--.--.--.--.--.--.--.--.--.--.--.--.--.--.--.--.--.--.--.--.--.--.--. ___ ___ __ __ __ | |__| |__ /\ |\/| /\ / | |\ | / _` | \__ | | | |___ /~~\ | | /~~\ /_ | | \| \__> _____| __ \__ | \__ __ __ ___ __ ___ __ | \__ / \ |__) |__ |__) /\ | | / \ |\ | /\ | | \______ \__/ | |___ | \ /~~\ | | \__/ | \| /~~\ |___ | __/ | __/ __ ___ ___ __ _____| -|- __/ /\ |\/| |__) | | |__ | |__ |__) | __/ /~~\ | | | |___ | | | |___ | \ |__/ _._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._ T H E B U I L D I N G B L O C K O F A N A L O G S Y N T H E S I Z E R S By The Harminator. If you want to understand how an analog synth works, you need to know about operational amplifiers, or op amps for short. Operational amplifiers were developed for analog computers to perform mathematical operations. That's right, before digital computers there were computers based on analog mechanisms based on mechanics and hydraulics. The oldest know analog computer is the Antikythera mechanism, a computer that could predict astrological positions and eclipses decades before they occured. The mechanism is dated around 100 BC. Nobody knows how it really works. ___________________________________________________________________________________ ___________________________________________________________________________________ ___________________________________________________________________________________ __________________ ________ _______________________________________________________ _______________ __/ \__ ____________ __/ \__ ___________ / __ \ __________ / \ \ _________ | \__/ | _________ | ___ | _________ | \ | _________ | \ | ___________\ \ / / ____________\ \___/ / _______________\ / __________________\_________/______________________________________________________ ___________________________________________________________________________________ ___________________________________________________________________________________ ___________________________________________________________________________________ ___________________________________________________________________________________ ___________________________________________________________________________________ ___________________________________________________________________________________ ___________________________________________________________________________________ In more recent times analog computers were used to calculate trajectories of guns and rockets in both the world wars. For instance the V2 rocket flight path was calculated using an analog computer. The early analog computers also used electrical 'mechanisms': operational ampli- fiers made with vacuum tubes. When digital computers took over in the 1950s, analog computers where hardly used, but the op amp turned out to be the most versatile electronic component. The op amp is built from different electronic components itself, but has a parti- cular behaviour that can be used to create many different electronic functionalies: it can amplify electronic signals, compare signals, invert them etc. In the late sixties op amps came onto the market in an integrated circuit package, a chip basically, and the modern synths were being created by the Bob Moogs of this world. The most prolific op amp, the μA741 by Fairchild Semiconductors, was created in 1968 and is still in production today. ___________________________________________________________________________________ _______________________________________________________ ____ ______________________ ___/ \ ____/ \ ___________________ ____/ \ ____/ _ \ __________________ ____/ | \ ____/ ___ | | | \ _______________ ____/ | | |__|_ | \ ______________ / __ / | _|_ \ _____________ / | | / | \ ____________ |\ |__| | /| ____________ | \ | | _| |_ ____/ | ____________ | \ |__| ___/ | ____________ \ \ | ____/ ___ / ____________ \ \ ____/ / \_/ _____________ \ \ ____/ ___ ___\ \ ______________ \ \ ____/ / \_/____\ | ______________ \ \ ____/ ___ ___\ \ ____| | ______________ \ \____/ / \_/____\ | ____|___/_______________ \ | ___ ___\ \ ____| | ________________________ \ | / \_/____\ | ____|___/_________________________ \|___\ \ ____| | __________________________________ \ | ____|___/___________________________________ | | ____________________________________________ _________________________________|___/_____________________________________________ ___________________________________________________________________________________ ___________________________________________________________________________________ ___________________________________________________________________________________