The Quadra is one of the first synthesizers to incorporate a microprocessor in its design, allowing you to produce a powerful body of sound and quickly change to a dramatically different sound with just a touch of a switch. One of the newest technological advances used in the Quadra is the tap-touch switch-an ARP exclusive. Each switch is an hermetically-sealed, electronically-latched, mechanical switch. This type of switch is extremely fast and highly resistant to failure. Another new and important design concept included in the Quadra is the user programmability of up to sixteen separate and distinct voices. Although fully programmed as shipped from the factory, you can edit, memorize, or erase any or all of the synthesizer parameters at any time. As you delve into the basic operational theory of the Quadra, you will discover that an immense amount of thought was required in the creation of this instrument. You will find numerous subtle live-performance human engineered features for which ARP is famous. This manual is intended to be your guide and should provide you with all the operational knowledge you need. If not, see your ARP Dealer or write or call ARP Instruments,. Inc. for further assistance.