1

I have a pair of USB-C active noise cancelling headphones, and I'd like to use them with the in-flight entertainment system of an airplane. A typical in-flight entertainment system comes with either a 3.5mm jack or a double-pronged jack for audio, as well as a USB-A female receptacle for power only.

Adapters from a double-pronged jack to a 3.5mm receptacle are very common, and so are adapters from USB-A male to USB-C female. But what seems to be impossible to find is a converter from either the double-pronged jack or the 3.5mm jack to a USB-A or USB-C female receptacle.

I understand that the 3.5mm jack contains an analog signal, which has to be converted to a digital signal for the USB output. Furthermore, power has to be drawn from a separate source to do that, but I can get power from the power-only USB-A receptacle on the plane.

Does the converter I need exist? This converter should have two inputs (USB male for power only, and 3.5mm jack or double-pronged jack for analog audio) and one output (USB female).

1
  • My idea would be to convert the analog signal to a digital signal (S/PDIF or I²S audio) first and then use some sort of capture device to convert this to something the DAC in an USB C headphone can understand. Ask hifimediy.com and report back.
    – chx
    Commented Jan 7 at 14:36

1 Answer 1

0

You will likely need something with enough compute to talk to the USB digital audio device presented by the USB-C connector, as well as an ADC to sample the analogue audio. This is a fairly complex device since it needs to run a full USB host stack.

I don't know of a product as such, but it could be done with a board like a Raspberry Pi with an audio input - either via a HAT or a USB line in adapter. That would need a small amount of software config to make it work.

1
  • Pi Zero + Zero4U usb hub + plugable USB sound card + active C female to A male adapter would do it. You would need to run a tiny program which replays the audio from the microphone in to the USB C headphones. Not the best audio quality for sure. There are other audio Zero hats which might be better.
    – chx
    Commented Jan 7 at 15:11

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.