Using a standard PC gaming / smartphone headset for passengers in a small plane There is a very similar question to this, but all answers and discussion pertain to just the PC headphones, and not headsets (the headphones with microphones). Gaming headsets have a boom mic and cable with dual connectors (pink/green), both 3.5mm, one stereo (for headphones), the other mono (for the mic). Standard smartphone headsets have a mic on the cable and a single 3.5mm TRRS (tip-ring-ring-sleeve) combo connector. There are plenty cheap ones with active noise reduction, decent audio quality on both headphones and mics, and more importantly, many people already have them. There are also plenty of Bluetooth headsets (with mics).
A possible solution would be building a Bluetooth adaptor that could plug into the intercom, and then pair with the passenger’s headset to allow them to communicate with others. Bluetooth frequencies are well outside the range of any of the nav/com systems, and even so, they would give the pilot a good excuse to avoid passenger distractions during departure /approach (by turning the Bluetooth transceivers off). Resourceful home builders could easily get the necessary electronics for the Bluetooth transceiver (and adjust the impedance as needed).
If the mic (and headphone) impedances are reasonably close, wouldn’t a simple cable adapter be all that’s needed to enable connection?
This is an interesting question. But, I don’t see what this solves. There are aviation headsets as cheap as $50. That is as cheap as gaming headsets. But, they are specifically designed for aviation to include passive noise reduction. There would be no advantage to using a gaming headset in aircraft.
The primary purpose of aviation headsets for the pilot is to provide clearer communication between the pilot and ATC. But, that purpose shares equal importance with the goal of hearing protection.
Small, General Aviation aircraft are very loud. But, aircraft have speakers and microphone handsets that make communication with ATC still possible. In decades past, headsets were not even worn in enclosed cabins. And, it has only been recently that the effects of noise has been considered a factor in fatigue. Unless the headset addresses the concern of noise reduction, it is of little benefit in the aircraft.
For passengers, noise reduction can be accomplished with industrial or firearm hearing protection. Non-crew member military personnel function with only standard earplugs aboard aircraft. Communication between personnel in the aircraft even with the doors open is accomplished through shouting over the ambient noise. As far as the pilot turning off a Bluetooth device to enforce “sterile cockpit” practices, that can already be accomplished as a built in function of the aircraft audio panel.
So, although a very simple adapter could be built to enable gaming headsets, cellphone headsets, and earbuds to be used in aircraft, it does not truly solve the problem you posed so far. And, it is not truly better than purpose-built aviation headsets. However, my purpose-built aviation headset is Bluetooth enabled, and can be used with a Bluetooth enabled computer like a gaming headset.