[Boatanchors] Want to use stereo headphones w/mono audio output

[Howie WA3MCK]

I need a circuit for a simple resistive balancing network to connect stereo
headphones for use with my monophonic boatanchor receiver.

I remember seeing one in popular electronics back in the late 60's early
70's.

Just shorting the tip and ring together on a 1/4" jack doesn't hack it.

My old Telex 610 headphones are not that comfortable, frequency response
sucks, and they  make my ears sweat and I go deaf temporarily when I take
them off...

Thank you
Howie WA3MCK