I would just use an op-amp. Direct couple its output to the headphone, with no DC blocking caps in the output stage. Build the offset circuit to manage the DC offset. Make a higher voltage power supply so you have enough output power.
Be prepared to be amazed.
Steve
"I am a licenced motorcycle instructor, I agree with dangerousbastard, no point in repeating what he said."
"read what Steve says. He's right."
"What Steve said pretty much summed it up."
"I did axactly as you said and it worked...!!"
"Wow, Great advise there DB."
WTB: Hyosung bikes or going or not.
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