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SUMIX is a modular audio summing/mixing system for modular synthesizers, initially targetted at the Eurorack format. It provides a range of facilities, features, and specifications comparable to mid-range professional audio mixing consoles, with specific additional features to match the modular synthesizer environment and usage.

The original SUMIX idea was for a monolithic 5-input stereo mixer. But this seemed to be an anethema within the context of a modular synthesizer! So while the original idea has been shelved/cancelled, the idea of an audio mixing system for the modular synthesizer lives on.

Goals and Objectives

First and foremost SUMIX is designed to be an open system, in that the full specs of the summing bus are published for all - DIY and commercial - to use freely.

Secondly, SUMIX should provide a low-noise and low distortion signal path from channel inputs to master outputs. Within the context of the modular synthesizer this requires careful attention to circuit topology, component choice, and architectural decisions.

Thirdly, a SUMIX system must be able to grow as the synthesizer grows. Growth both in terms of the original housing, and on to additional cabinets, even to modular synthesizers of differing formats.

Fourthly, SUMIX is designed to be cost-effective. Standalone mixing desks achieve fantastic economies of scale due to the tightly-integrated nature of the design. A modular mixer is not so blessed, yet customers remain cost-conscious. There is a careful trade-off between the convenience and cost of an integrated audio mixing system compared to an external mixing desk.

My hope is that SUMIX achieves all this.


System Architecture - The various components and how they can fit together

Specifications - Detailed electrical and mechanical information

02.04.2016. 23:20