The plan at the moment is to.
Unbalanced summing box.
Figure 1 shows the required network for sources with unbalanced outputs.
Acb 1 jack box stereo headphone acb 2 jack box dual rca jacks acm 3 amplitude component monitor.
This is routed to the single output jack.
Two resistors tie each input together to the junction of a third resistor which connects to signal common.
I found this simple schematic detailing a summing box for balanced audio signals you will find the schematic photos and a build video.
This is routed to the single output jack.
Unbalanced summing box figure 1 shows the required network for sources with unbalanced outputs.
The resistor values can vary about those shown over a wide range and not change things much.
Figure 1 shows the required network for sources with unbalanced outputs.
I bought a rather inexpensive hobby box for about 2 and proceeded first to drill three holes in it.
I have some ideas about how to do this but any insight would be greatly appreciated.
Now that the audio engineering society has adopted the pin 2 is hot standard the question of what to do with pin 1 is being addressed.
Check out the video above for a quick run through of how i built my 16 channel summing box.
Altering the balanced summing box to an unbalanced one seems rather simple but i want to properly handle the summed impedance.
Most analog summing designs take a number of mono inputs and assign them to the stereo bus via either pan pots or l c r switches.
Two resistors tie each input together to the junction of a third resistor which connects to signal common.
I want to sum them into 2 balanced channels each containing 4 piezos.
I made a rather crude unbalanced audio summing box a couple of nights back.
The resistor values can vary about those shown over a wide range and not change things much.
The extron asa 141 audio summing adapter is a convenient single cable solution for combining two channel stereo audio into a balanced or unbalanced mono audio signal it is ideal for summing stereo signals for use in mono pa systems in churches halls arenas stadiums and other environments where stereo signals would result in cancellation.
My plan is to use it as the basis for my design modifying it to sum unbalanced signals.
13 03 2020 alan leave a comment go to comments.
A recommended practices document is being created covering interconnection of professional audio equipment.
The resistor values can vary about those shown over a wide range and not change things much.
I will take care of balancing the signals after the box with 2 high impedance di boxes that i already have.
Unbalanced summing balanced summing output impedances introduction.
Luckily passive summing is a pretty simple concept and one that s very wallet and diy friendly to achieve.
Unbalanced audio summing box.