Cable should is fed directly from your laptop source (both channel, no resistors BEFORE the cable, resistors must be at the end only ) and each channels end connected to the summing resistor. Join the other end of the resistors and this is your mono output wich goes directly to your amp input (XLR connector)
Hope its clear now
Hope its clear now
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Sure.
Use shrinck tubes for isolation and mechanical stress relief. Try the cable before you shrinck.
As to your earlier questions, as long as the output of your source can deliver 2V you do not need any other cable. From a source that can deliver the power to feed 200 ohm (usually only headphone or speaker outputs are capable of that) you can use two 100 resistors. For example, a source capable of driving 600ohm is more than happy driving two 475ohm resistors but would be grossly overloaded driving two 100 ohm resistors. Try to reread what i wrote in my earlier posts and you will understand and be able to judge yourself what works and why.
Use shrinck tubes for isolation and mechanical stress relief. Try the cable before you shrinck.
As to your earlier questions, as long as the output of your source can deliver 2V you do not need any other cable. From a source that can deliver the power to feed 200 ohm (usually only headphone or speaker outputs are capable of that) you can use two 100 resistors. For example, a source capable of driving 600ohm is more than happy driving two 475ohm resistors but would be grossly overloaded driving two 100 ohm resistors. Try to reread what i wrote in my earlier posts and you will understand and be able to judge yourself what works and why.
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From doing some research it seems that laptop or phone jacks don’t reach this voltage requirement as a lot of the sites I’ve looked at suggest that they can make +/- 1.5v to 3v so there may be a need for more cable or some sort of protection, potentially like the 20k resistor shown in previous designs?
a different cable will not help. The 20k resistor would be additional load and only worsen the situation. This resistor is only needed in the very rare case (bad design) that provides no other dc path to ground for the coupling cap.
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So as long as I have ground from the trs to the xlr there is no need for the 20k resistor just two 1k resistors for the hot and cold of the trs?
For the trs to xlr I’m going to repurpose some old microphone cable and swap the terminals for the ones I want and add the resistors on the end from my knowledge this doesn’t have any additional load impedance added to it but I will check the impedance of the wire once cut with a multimeter to see if it has over the standard amount
I’ve made one of the summing wires and wanted to see if the readings I’ve got for continuity are to be expected. I linked terminals 1 and 3 on the xlr end and wired the ground to these. Continuity from the sleeve to pins 1 and 3 read 0 which was to be expected. With the tip and ring I added the 1k resistors to them at the xlr end. I tested the continuity after adding the resistors in. For both the tip and ring with the resistors the continuity read around 980 and when they were joined to pin 2 the continuity read around the 2k mark. Is this because of the inclusion of the resistors? I also measured the continuity across the tip and ring and this measured at the 2k mark as well. Does this mean that the signal will from from the tip back down into the ring and vice versa or is this expected?