Created of multiple, independent, easily integrated component pieces that can be added or changed out easily to enhance functionality or add features. Several multi-channel amplifiers are using modular designs allowing a consumer to purchase an amplifier with two channels and add additional channels at a later date. Preamplifiers are being created featuring modular designs allowing additional functions, such as digital-to-analog conversion or video distribution, to be added individually at a later date. The advantage of modular construction is that equipment can be more easily built to the exact specifications of the consumer while allowing the consumer flexibility for the future.