You gave three reasons to not produce stereo equipment for aircraft.

1: One can get lost in the music... to which I ask whether it matters
whether it is in stereo or not.

2: Cost of stereo... to which I ask whether the second channel really
is that much more expensive. In the case of a headphone, I don't see
where the extraordinary expense would come from.

3: Compatibility... well, ok if you are designing entire panels (which
I assume RST is). But there are compatibility issues with mono too.
If others are producing stereo, you have the same issues.

I would also point out an advantage to stereo, used properly (which I've
actually never seen)... and that is the ability to put the intercom
(mostly) in one ear while ATC is (mostly) in the other, or to put Com1
on the left and Com2 on the right (which would be a godsend when trying
to get the ATIS or monitoring CTAF while staying with ATC).

Jose
r.a.owning trimmed - I don't follow that group
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