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To avoid massive build errors, make sure the BOM Revision you follow matches the Revision of the PCB you are building!! The 2TA1 Resistive Summing Mixer Entire Bundle is a complete kit bundle that contains all of the parts and components required to complete a 2 X 2:1 summing mixer. This is a simple, balanced, resistive summing mixer using 0.1% precision resistors. There are no transformers or active circuitry involved. This device is not designed to be a microphone mixer. It is intended to mix line level signals only like preamp outputs. The 2TA1 is a great solution for combining the A and B bus outputs of the SumBus ACA. Each end panel of the 2TA1 is identical so it can be used to mix two isolated sets of two signals down to one, hence 2 X 2:1. You can combine two snare mic preamps on one end and two kick mic preamps on the other end etc. With the 1k precision resistors, you can expect a 6dB loss per source. That may be confusing so let me try to explain. With the output of only one 0dB device connected, the 2TA1 will have essentially no loss in level. Once you connect the output of a 2nd device (that is passing no signal) the 2TA1's output will drop by 6dB. If the 2nd device's output is also 0dB, the output of the 2TA1 will be 0dB. Since we are doubling the power there is a 6dB increase which offsets the previously stated loss. Put that in your pipe and smoke it!! Above results are into a high Z load. When driving a 600 ohm load the loss will be greater. The phase, frequency response and THD+noise will all still remain ruler flat. In a custom CAPI® Clamshell enclosure 4 5/16" wide X 5 3/16" long X 2 7/16" high

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