The amplifier circuit is inverting, so wiring it as intended and shown (with speaker red on ground) restores absolute phase.
Attach your speakers normally - red to red, black to black.
Both ways will work fine. If one was forced to choose, wire as shown the photo.
The document that has exactly what you are asking about is the schematic. :) The PCB is labeled with the parts locations, and the numbers on the PCB match the schematic.
As for identifying the resistors, use your multimeter set to ohms and measure them.
Also remember you can click into the photo for high resolution.
Position the tabs down towards the speaker posts, as they will not obscure the RCA’s center post once there is wire attached.
Can you bi-wire the speaker? Yes. Can you use the remaining speaker posts to do it? No. When using the ACA in bridge mode (feeding a signal through the XLR or using the white RCA and the bridge switch) the output is taken from both amplifier PCBs per speaker. Because of this, the red speaker posts, being ground, must stay empty.
The ART box you mention is a transformer based RCA to XLR converter? That should work nicely.
Good catch! Fixed. :)
Making this circuit balanced will require something on the output to take SE to BAL, the most straightforward is to use a transformer for each channel. This is considered the reference document for doing that - http://www.jhbrandt.net/wp-content/uploa...
However, much easier than that would be to let the ACAs do the phase splitting and use the ACAs as RCA input bridge monoblocks. See step 55 of the 1.6 guide - Amp Camp Amp V1.6 Build Guide
You can mount both to one heatsink. There will be no issues. :)
A better place to discuss questions like this is here - https://www.diyaudio.com/forums/pass-lab...
Plug for the rear switch hole if you choose to not use the rear switch.
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