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Comment by Kirby64 | Hacker News Reader

That "cheap passive adapter" has a ridiculous amount of complexity (both in the dongle, and in the chip you would have to connect it to to make it functional) that you're overlooking. You can't just 'route the DAC in the speaker to the Type-C connector'. That's not how these systems are built at all, and certainly not something that would be functional even if you could just route the speaker DAC to a 3.5mm connector or Type-C connector.

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The USB standard has provision for analog output through the MUX, and all compliant MUX/controller chips will have implemented this.

https://www.anandtech.com/show/10719/usbif-publishes-audio-o...

If this is so non-trivial, Chinese OEMs like Huawei have in fact succeeded in analog output. This is despite the fact that their receptacles are on a 50mm long flex PCB, you don't need another 2 signal layers or an extra daughterboard.

The laws of physics are the same everywhere across the world. Just because Apple is incompetent, it does not imply everyone else is.

You're talking to someone who works with folks on the USB-IF committee. Analog output through the DP/DN/SBU pins is not standard these days. A mux isn't even necessary in many implementations. Also, this functionality in USB Type-C is straight up deprecated. Just because it's technically possible (and sure, I agree, it is technically possible) doesn't mean it isn't more costly, less efficient, and wasteful vs. just putting the codec directly in the USB-C to 3.5mm dongle.

Here's the rationale than USB-IF gave in the ECN:

>> Few hosts support analog audio accessory. Those that might could be confused when connected to a device supporting corrosion mitigation, but no detrimental behavior should be seen. This should be a corner case of a corner case so likely zero to very low ppm of this condition. Note, any compliant host that supports analog audio accessory today is also required to support digital audio accessories, so there should be no impact to users."

> That "cheap passive adapter" has a ridiculous amount of complexity (both in the dongle,[...]

I believe they are referring to Audio adapter accessory mode. What is so complex about two resistors on the CC1 and CC2 pins?

Sure, if you use the audio adapter accessory mode, you can just get CC1/CC2 resistors. But then you just push a ton of complexity (even more-so than the standard codec for headsets) into the device. You need additional analog muxes above and beyond the codec, which aren't free. Nobody implements this anymore, cause it's much easier to just shove the codec into the dongle itself. Also, it's deprecated as of the latest USB-C specifications (precisely because nobody uses it now).

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