Sumtiple

Precision adder and active multiple

A 3-input precision adder is combined with a 3-output active precision multiple. The multiple input is normalized to the adder output, so you can have 4 adder outputs total.

Very low gain and offset error make this a perfect tool for adding and splitting pitch CVs, but it is also a great general purpose tool. Of course works for audio as well.

A RGB-LED shows the adder output signal (red positive, blue negative) and multiple input (green, positive only)

You can multiply an input by 2 or 3, by patching the multiple outputs to the adder inputs.

Adder:

Maximum offset 0.2mV, 0.24 cent
Gain error of maximum  0.025%
Input impedance: 47k
Output impedance: ~1 Ohm

Multiple:

Maxiumum offset: 0.1mV, 0.12 cent
Gain error of maximum 0.1mV @10V input = 0.001%
Input impedance: 1 Meg
output impedance: ~1 Ohm

Picture by Paul Pape

https://tubbutec.de/sumtiple