Technical Definition of Digital Summing?

[MatsonMusicBox]

Hi All - I'm looking for a technical definition here. Speaking strictly in terms of staying ITB - all digital ... do you think the term "Summing" means:

1. A process that, despite its name, has a broader meaning that includes "all the math necessary" for a DAW to combine the tracks, buses, etc. at their various levels into a final mix ... or
2. That as its name indicates, only includes those parts of the above that are purely "summing" in the mathematical, literal sense - that is ...addition operations only.

I'm interested in thoughts or any formal definitions anyone has or can point to.

[Matt Syson]

Hi
Not really answering your question but to the computer it is only number crunching similar to a 'database'.
Granted it is 'streamlined' so that events happen at the correct time but at the heart it is just numbers.
Matt s

[JohnRoberts]

In simplest terms and to directly mimic an analog sum, it is the simultaneous add of multiple digital input data streams, into a single digital output stream.

I would expect differences between floating point and fixed point math implementations, and perhaps time offsets due to serial vs. parallel organization of much digital hardware. Processing complexity can increase if sample rate conversions and fader/pan multiplies are involved. The gain tweak will be fast (in digital clock time) but the conversion may get messy.

In theory such a sum should be loss-less and arbitrarily accurate, even better than analog. In practice, results and opinions vary.

JR