One of the complaints that I have had from the start with our airplane is the inadequate audio system. This is no surprise, since the audio system was one that I understood the least about, and it was the most difficult to integrate. Further complications came from our project coming with the Flightcom intercom already, so I never did any research to select the best intercom for our application. The end result was that I had to adjust the squelch every time I applied takeoff power. To be fair, our cabin is exceptionally noisy; I wouldn’t even consider flying in it without a headset and/or earplugs. I’m sure that the 403 is well-suited for an airplane with an average noise level. Research led me to the PM3000, and discussions with the folks at PS Engineering led me to believe that it would be a better choice. So did I call them up and buy one? No, actually. There are several sub-models of the PM3000, depending on how the unit is set up to isolate. I wanted the one that would allow us to isolate the back seaters from the front seaters, and that model number is 11932.
From the front, it looks like a pretty straight-forward swap. Just drill a few new holes, and be glad that the new one is bigger than the old one! From the back though, there is this:
Hmmm… it would have been handy if the gender of the d-sub pins was the same. Fortunately, we have handy access at the top of the instrument panel:
It ended up taking me a couple of afternoons to get everything squared away. One challenge was removing the stereo/mono toggle switches that the Flightcom had required (for reasons unknown to me). Another was routing wires for a second audio input, which is to be used by the back seat passengers when they are isolated to themselves. While I was in there, I considered a few options for integrating Bluetooth, and/or a USB port that would be able to charge my phone and use it for audio content. I have this arrangement in all of our cars, and it would be handy to have in the plane too. I have a circuit candidate on hand, but it needs more testing and modification before I trust it enough to make a permanent installation. It was very inexpensive and not intended for this kind of use.