How to convert a headphone out to mic out?


My purpose is to play my digital piano while connecting its audio output to my phone to send the sound in the phone call. I have jack splitters (or duplicaters maybe idk), anyway I can double the sound coming from the piano, letting one to be heard from headphones, one to send in the phone call via the mobile phone.

The problem is, when I plug the cable between the digital piano and the phone, the phone handles the connection as a headphone is plugged, but I want it to recognize as a mic is plugged instead.

I don’t know about how mic connections and headphone connections differ, but we all know that some headphones have also mic connection to the phone built-in. So there must be some way of making the output of the digital piano work as a mic connected to phone (making a custom cable maybe).

Any idea is appreciated, I don’t know the basics of anatomy of jacks, headphone outs, mic connections, line outs, etc, I only use them.

Thanks so much

Does the Splitter’s insertion into the cable-chain make any difference? (I realize that, without it, you can’t hear what you’re playing, correct? But can the other person hear it over the phone?)

Also, you know about Stereo vs Mono jacks, yes? This is a stereo-jack with two Black Bands around it (for Left and Right channels).

A Mono Jack will have one band instead of the above two.

I wonder if Mono vs Stereo makes any difference? (I wonder if you’ve mixed a Stereo Splitter with a Mono Cable, or vice versa.)

Each hardware ‘rig’ might be too unique to easily recreate - your type of keyboard, your phone, etc. But hopefully this is a Stereo-vs-Mono plug issue, or a Splitter issue.

The headset I have for a computer with a mic has two plugs color coded pink & green.
Both look like the image posted by Christine . I suspect there are internal differences.

Do you know if your phone is supposed to be able to use a mic in the jack you are pluging it into ?

I know the headphone/mic set I have for my telephones cell or home is smaller & mono . That is the only kind that will plug into the jack on the phone.
I haven’t looked for a stereo one . They may be available but the phone would need to support stereo.
IMO you are going to need to have the jack to the phone correctly wired.
I don’t know how to do that.
The mobile phone is going to need to accept the signal coming from the jack like it is connected to a phone headset with a mic. Further it will need to accept it as the mic. I don’t know is you can get the headphone to work at the same time or not.
Also the signal can’t be more than the mic would have if you were just talking into it . Or not much more anyway.
I suspect the piano amplifies the sound . You will need to get the signal before this amplification . In other words the mobile phone needs to work as the amplifier just like it would with the non amplified mic it would normally use in the jack.
I’m not an expert but the above should be correct.

What phone do you have? Some of them only support headphone out, while others will support headsets with microphone.