I shared some of this in the DickHamill Meteor 2021 thread, but has since it has come up in both places.
Xenon75 asked me
"I was wondering if you would be willing to share how you wired the external amp into the power of the game and how you toggle between the original and arduino? It is the last place on mine that I don't know how to do properly. Thanks so much!"
PinballHelp came up with a great way to add a switched power outlet so that the amp turns on and off with the rest of your machine. The best part is, you probably have all the parts on hand needed to do this.
Next is wiring up the switch. It's set up to allow you to either switch a single input between two possible outputs, or switch 2 inputs between a single output. For this, we are going to set it up in the latter configuration. You can see when looking at the switch, the outside row of contacts are both labeled 'On'. We can think of those as inputs, while the center contacts are outputs.
First thing you need is 2 wires, one going from the center terminal and one of the outside terminals. My picture has 3 wires because I was looking at the wrong jumper when I originally set this up, but the extra wire doesn't hurt anything, and I had some long cables for hooking up ESCs from and old drone project that worked perfect for my needs. This is going to connect up to J3 on your RoyGBev board to toggle between the standard code and the 2021 code by either connecting the 2 pins as a jumper for 2021, or leaving them disconnected for 1979.IMG_1913 (resized).JPG
If you just want to use speakers in the head and a 2 channel amp, wire then just as you would any normal speaker and you are good to go, nothing else needed.
If you want to use the cabinet speaker as a subwoofer, in the second picture you can see we are using the toggle to choose what signal is getting sent to the cabinet speaker. IMG_1914 (resized).JPG We are using 6 pins here for the speaker, and I made a little spreadsheet in excel to show where each pin should be connected to.Capture (resized).PNG Wire the center output contacts to go directly to your 6.5" speaker. Wire the outputs from your subwoofer output of the 2.1 channel amp to the side of the switch you have going to J3. Wire what was the old speaker inputs from your SB-200 board to the side of your selector switch where you left an open pin.
Setting it up in this manner allows you to toggle the game code, and the speaker output from the same switch (remember to turn off the machine before toggling). If you use spade crimps for the speaker connection, it's really easy to remove if you ever want to put the machine back to stock, or move it to another machine.